explain xkcd - User contributions [en]

2965: Chili Tornado Quake

2024-07-30T05:49:28Z

Blue in real life: transcript

{{comic
| number = 2965
| date = July 29, 2024
| title = Chili Tornado Quake
| image = chili_tornado_quake_2x.png
| imagesize = 302x252px
| noexpand = true
| titletext = Buildings constructed from softer materials were damaged by chili pepper impacts to the storm's high Richter-Fujita-Scoville-Mohs hardness rating.
}}

==Explanation==
{{incomplete|Created by a TREMBLING GHOST PEPPER - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
:[Cueball, a news reporter, next to headline reading "Breaking News", over an image of a tornado striking a building, and two chilis flying through the air, with pieces of the building flying off, along with cracks in the ground from an earthquake]
:Cueball: A tornado that struck a chili pepper processing plant during an earthquake was rated 55,000 on the Richter-Fujita-Scoville scale.

{{comic discussion}}
[[Category: Food]]
[[Category: Tornadoes]]
[[Category: Earthquakes]]

2963: House Inputs and Outputs

2024-07-25T06:07:50Z

Blue in real life: /* Transcript */ fixed spacing

{{comic
| number = 2963
| date = July 24, 2024
| title = House Inputs and Outputs
| image = house_inputs_and_outputs_2x.png
| imagesize = 740x684px
| noexpand = true
| titletext = People think power over ethernet is so great, and yet when I try to do water over ethernet everyone yells at me.
}}

==Explanation==
{{incomplete|Created by a possible reference to [[1037: Umwelt]] in panel 16 - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

This is another comic in the series of comics that use a {{w|confusion matrix}}, similar to [[2420: Appliances]], [[2813: What To Do]] and [[1890: What to Bring]].

{| class="wikitable"
|+ {{Citation needed}}
|-
! !! Well !! Garage !! Power lines !! Front door !! Septic tank
|-
| Fresh water (Input) || The purpose of a well is usually to pump fresh water into the home, primarily for drinking or washing. || This would not me helpful at all, and would more than likely destroy your car. || Water either shouldn't, or cannot be carried through electrical lines. || Many people prefer to control the amount of water they get, and the water may damage things inside the house. || Most people don't want anything they drink to contain(or go through pipes that have contained) sewage.
|-
| Cars (Input/Output) || Most cars manufactured in recent years can't fit inside a well. || Garages are in fact built for the storage of cars and other similarly-sized vehicles. Placing a car in one will both help protect it from the elements and make it easier to access from inside your own home. || As of yet, cars cannot be transferred through power lines and require roads to travel on. However, this could significantly reduce travel costs. || Most cars can’t fit through doors. ||
|-
| Electricity (Input) || This would contaminate your water supply. || No. || Power lines are designed to facilitate the connection of individual homes to the broader local power network. || A majority of people prefer their house to be solid and not made of ash. || ...
|-
| People (Input/Output) || This panel is not a black hole, and is instead from the view of someone inside the well. Being inside a well is obviously not an ideal situation to be in{{Citation needed}}. || Though not outright designed for it, a person can enter and exit their home through the garage door just fine, provided the garage has an internal door to the rest of the home. Not the best way to welcome guests though. || ... || The front door of a home is designed for entry and exit of humans and similarly sized items. || In general, people find crawling through waste unwanted. Also, the septic tank is not connected to the street.
|-
| Sewage (Output) || Sewage in drinking water can cause disease. || ... || As Knit Cap demonstrates, this would not be the most convenient idea. || ... || The purpose of a septic tank is to transport sewage from the home where it is processed elsewhere, usually to a sewage treatment plant.
|}

The title text references {{w|Power over Ethernet|Power over ethernet}}, first implemented in the early 2000s, which passed electric power along with data on twisted-pair Ethernet cabling. This was a welcome development, as it removed the need for many network-connected devices to have independent power supplies. While networked water delivery ("running water") is also a welcome development, doing so over ethernet cables would be an unmitigated disaster, and Randall would get off easy if he were merely to be yelled at.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

[A 5x5 grid of squares.
The columns are labeled: Well, Garage, Power lines, Front door, Septic tank. Each row's label has an arrow and a house next to it.
The rows are: Fresh water (horizontal arrow towards house), Cars (two-directional horizontal arrow and house), Electricity (horizontal arrow into house), People (two-directional horizontal arrow and house), Sewage (vertical arrow out of bottom of house).]

Well, Fresh water: [green]

Garage, Fresh water: [red]

Power lines, Fresh water: [red]

Front door, Fresh water: [red]

Septic tank, Fresh water: [red]

Well, Cars: [red]

Garage, Cars: [green]

Power lines, Cars: [red]

Front door, Cars: [red]

Septic tank, Cars: [red]

Well, Electricity: [red]

Garage, Electricity: [red]

Power lines, Electricity: [green]

Front door, Electricity: [red]

Septic tank, Electricity: [red]

Well, People: [red]

Garage, People: [green]

Power lines, People: [red]

Front door, People: [green]

Septic tank, People: [red]

Well, Sewage: [red]

Garage, Sewage: [red]

Power lines, Sewage: [red]

Front door, Sewage: [red]

Septic tank, Sewage: [green]

{{comic discussion}}

[[Category:Comics with color]]
[[Category:Charts]]

2963: House Inputs and Outputs

2024-07-25T06:04:38Z

Blue in real life: /* Transcript */ started transcript

{{comic
| number = 2963
| date = July 24, 2024
| title = House Inputs and Outputs
| image = house_inputs_and_outputs_2x.png
| imagesize = 740x684px
| noexpand = true
| titletext = People think power over ethernet is so great, and yet when I try to do water over ethernet everyone yells at me.
}}

==Explanation==
{{incomplete|Created by a possible reference to [[1037: Umwelt]] in panel 16 - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

This is another comic in the series of comics that use a {{w|confusion matrix}}, similar to [[2420: Appliances]], [[2813: What To Do]] and [[1890: What to Bring]].

{| class="wikitable"
|+ {{Citation needed}}
|-
! !! Well !! Garage !! Power lines !! Front door !! Septic tank
|-
| Fresh water (Input) || The purpose of a well is usually to pump fresh water into the home, primarily for drinking or washing. || This would not me helpful at all, and would more than likely destroy your car. || Water either shouldn't, or cannot be carried through electrical lines. || Many people prefer to control the amount of water they get, and the water may damage things inside the house. || Most people don't want anything they drink to contain(or go through pipes that have contained) sewage.
|-
| Cars (Input/Output) || Most cars manufactured in recent years can't fit inside a well. || Garages are in fact built for the storage of cars and other similarly-sized vehicles. Placing a car in one will both help protect it from the elements and make it easier to access from inside your own home. || As of yet, cars cannot be transferred through power lines and require roads to travel on. However, this could significantly reduce travel costs. || Most cars can’t fit through doors. ||
|-
| Electricity (Input) || This would contaminate your water supply. || No. || Power lines are designed to facilitate the connection of individual homes to the broader local power network. || A majority of people prefer their house to be solid and not made of ash. || ...
|-
| People (Input/Output) || This panel is not a black hole, and is instead from the view of someone inside the well. Being inside a well is obviously not an ideal situation to be in{{Citation needed}}. || Though not outright designed for it, a person can enter and exit their home through the garage door just fine, provided the garage has an internal door to the rest of the home. Not the best way to welcome guests though. || ... || The front door of a home is designed for entry and exit of humans and similarly sized items. || In general, people find crawling through waste unwanted. Also, the septic tank is not connected to the street.
|-
| Sewage (Output) || Sewage in drinking water can cause disease. || ... || As Knit Cap demonstrates, this would not be the most convenient idea. || ... || The purpose of a septic tank is to transport sewage from the home where it is processed elsewhere, usually to a sewage treatment plant.
|}

The title text references {{w|Power over Ethernet|Power over ethernet}}, first implemented in the early 2000s, which passed electric power along with data on twisted-pair Ethernet cabling. This was a welcome development, as it removed the need for many network-connected devices to have independent power supplies. While networked water delivery ("running water") is also a welcome development, doing so over ethernet cables would be an unmitigated disaster, and Randall would get off easy if he were merely to be yelled at.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

[A 5x5 grid of squares. The columns are labeled: Well, Garage, Power lines, Front door, Septic tank. Each row's label has an arrow and a house next to it. The rows are: Fresh water (horizontal arrow towards house), Cars (two-directional horizontal arrow and house), Electricity (horizontal arrow into house), People (two-directional horizontal arrow and house), Sewage (vertical arrow out of bottom of house).]
Well, Fresh water: [green]
Garage, Fresh water: [red]
Power lines, Fresh water: [red]
Front door, Fresh water: [red]
Septic tank, Fresh water: [red]
Well, Cars: [red]
Garage, Cars: [green]
Power lines, Cars: [red]
Front door, Cars: [red]
Septic tank, Cars: [red]
Well, Electricity: [red]
Garage, Electricity: [red]
Power lines, Electricity: [green]
Front door, Electricity: [red]
Septic tank, Electricity: [red]
Well, People: [red]
Garage, People: [green]
Power lines, People: [red]
Front door, People: [green]
Septic tank, People: [red]
Well, Sewage: [red]
Garage, Sewage: [red]
Power lines, Sewage: [red]
Front door, Sewage: [red]
Septic tank, Sewage: [green]

{{comic discussion}}

[[Category:Comics with color]]
[[Category:Charts]]

Talk:2963: House Inputs and Outputs

2024-07-25T05:55:28Z

Blue in real life: yw

what in the heckoslovakia is panel 16 [[Special:Contributions/172.71.147.216|172.71.147.216]] 02:18, 25 July 2024 (UTC)
:I can only assume that it's from the perspective of someone inside the well looking upward toward the outside world. [[User:OmniDoom|OmniDoom]] ([[User talk:OmniDoom|talk]]) 02:23, 25 July 2024 (UTC)
:: It's a reference to The Ring (リング) films and books. This distorted view from the inside of the well is an iconic part of the franchise's imagery, and, in minimal-spoilers form, its appearance suggests that someone has watched the cursed tape and should now expect a visitor to arrive from that well in seven days. (Definitely a red intersection) [[User:Scorpion451|Scorpion451]] ([[User talk:Scorpion451|talk]]) 02:52, 25 July 2024 (UTC)
::: more at https://en.m.wikipedia.org/wiki/The_Ring_(franchise) aside holy gosh! I was expecting to link to IMDB for like two or three movies. /aside the trailer at https://m.imdb.com/title/tt0298130/ starts with an a 1950-1990 ish USA telephone ring. It's been a while since I saw it and the ring referring to a telephone not magic ring is starting to sound familiar. SDT
:::: which is too much detail. "Panel 16 refers to a horror film" is not enough info SDT [[Special:Contributions/172.70.134.102|172.70.134.102]] 04:06, 25 July 2024 (UTC)
[[Special:Contributions/172.70.134.100|172.70.134.100]] 03:58, 25 July 2024 (UTC)
I'm assuming that a table would probably be best for this comic, but tbh I don't know how to make one and it's kinda late for me. [[Special:Contributions/162.158.137.212|162.158.137.212]] 02:48, 25 July 2024 (UTC)
:Update: thanks to whoever made the table [[Special:Contributions/141.101.109.192|141.101.109.192]] 03:32, 25 July 2024 (UTC)
:::You're welcome :) I had to look at Wikipedia's tutorial to make it - [[User:Blue in real life|Blue in real life]] ([[User talk:Blue in real life|talk]]) 05:55, 25 July 2024 (UTC)

2963: House Inputs and Outputs

2024-07-25T04:41:23Z

Blue in real life: Since i have to put an edit summary every time did u guys know about ꙮ? This character, representing a "many-eyed seraph", was drawn by a Russian Orthodox monk in 1429, and added to Unicode in 2008.

2963: House Inputs and Outputs

2024-07-25T04:37:10Z

Blue in real life: if we're doing this bit then

2963: House Inputs and Outputs

2024-07-25T03:31:43Z

Blue in real life: one more

2963: House Inputs and Outputs

2024-07-25T02:57:20Z

Blue in real life: Input/Output

2963: House Inputs and Outputs

2024-07-25T02:56:17Z

Blue in real life: table

2957: A Crossword Puzzle

2024-07-10T21:25:54Z

Blue in real life: 2 sentence explanation

{{comic
| number = 2957
| date = July 10, 2024
| title = A Crossword Puzzle
| image = a_crossword_puzzle_2x.png
| imagesize = 740x937px
| noexpand = true
| titletext = Hint: If you ever encounter this puzzle in a crossword app, just [term for someone with a competitive and high-achieving personality].
}}

==Explanation==
{{incomplete|CreAAAAAAAAAted by AAAAAAAAAAA BOT - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

This is a crossword puzzle where every single answer consists only of the letter "A". On a surface level, however, the answers seem extremely difficult, with some involving base conversions, and some involving the wordplay typical of the crossword style.

===Across===
* 1 across. Famous pvt. wilhelm quote: Reference to the {{w|Wilhelm scream}}.
* 11 across. An IPv4 record is an "A" record, an IPv6 record is four times the length and is designated an "AAAA" record.
* 15 across. A [https://en.wikipedia.org/wiki/Vigenère_cipher "Vignère Cipher"] translates the original text by the distance from A from the key, letter by letter. For instance, if the plaintext is "XK" and the key is "CD", the C shifts X 2 forward to become Z, and the D shifts K 3 forward to become N, yielding a ciphertext of "ZN". Since the ciphertext and the key are the same in this case, decryption just shifts all the letters back to A, akin to subtracting a number from itself and getting 0.
* 16 across. A [https://en.wikipedia.org/wiki/AAAA_battery "AAAA battery"] is a 1.5V battery that measures 8.3mm in diameter, 2.2mm smaller than the more common AAA battery.
* 17 across. The {{w|A-10 Warthog}} is a well-known attack aircraft. Here, A-10 has been turned into AAAAAAAAAA (ten As).
* 18 across. Aphantasia is the inability to visualize. Following the instruction, we determine that '''A'''ph'''a'''nt'''a'''si'''a''' gives us the word "aaaa".
* 20 across. {{w|Minas Tirith}}. In Mario games you typically use the A button to jump. In games where you don't press a button to move (e.g. games with a joystick) then ascending a vertical structure would probably just take the A button. This clue was possibly inspired by the {{w|A-button challenge}} / [https://ukikipedia.net/wiki/A_Button_Challenge A Button Challenge].
* 21 across. {{w|A4 paper}} (here written as AAAA) is the default size in Europe. It is approximately 0.24" narrower and 0.71" longer than the 8.5"x11" paper used in the United States, and due to having an aspect ratio of 1:sqrt(2), can be cut in half to create two half-sized sheets with exactly the same aspect ratio.
* 22 across. Unary's when you get to use just the one symbol. E.g. 32 in unary would be 11111111111111111111111111111111. The first four strings in unary, if you used A as the first (and only) symbol, would be A, AA, AAA, AAAA.
* 23 across. {{w|Lysene}} is an amino acid, with codons AAA and AAG (presumably the former is meant here).
* 24 across. [https://www.ecfr.gov/current/title-40/chapter-I/subchapter-C/part-63?toc=1 "40 CFR Part 63"] refers to federal air pollutant regulations. The subpart for "asphalt processing and asphalt roofing manufacturing" is AAAAAAA.
* 25 across. The highest {{w|credit rating}} for bonds is AAA.
* 26 across. The {{w|Audi A5}}, here written as AAAAA.
* 29 across. A reference to Howard Dean, an American Democrat who ran for the party's nomination in 2004. He famously [https://www.youtube.com/watch?v=l6i-gYRAwM0 yelled at a rally] in a way that was thought to be bizarre and which, it is thought, doomed his campaign.
* 36 across. I.e. "open up". Or an expression of pain; particularly the only kind you can make with dental tools in your mouth. (As Autechre put it: [https://youtu.be/UppsLKz1iD4 "Now, I don't want you to panic... just lean back and relax."])
* 38 across. AAA the IATA code for the airport
* 41 across. Macaulay Culkin's review of aftershave: Famously in the movie {{w|Home Alone}} he puts it on because he's home all alone and dislikes it, emitting a scream, which could be transcribed like A's.
* 50 across. The call which Elsa hears in Frozen 2 is a sequence of four notes which resemble the Dies Irae. The sequence is sung entirely with an open rounded vowel sound, or a soft "a" sound.
===Down===
* 1 down. {{w|AaAaAA!!! – A Reckless Disregard for Gravity}} - notably the title is commonly extended in promotional material beyond 6 A's.
* 2 down. 10101010 10101010 10101010 in binary is equivalent to "AAAAAA" in hexadecimal.
* 3 down. the Pixel 6a was released in July 22. Stylized in this puzzle as "AAAAAA"
* 4 down. 5 times better than {{w|A1 steak sauce}} would be A5, stylized in this puzzle as "AAAAA"
* 5 down. The decimal number 43690 converted to hexadecimal is AAAA
* 26 down. A high budget video game is usually referred to as A Triple-A game, or AAA
* 29 down. `echo -n AAAAAAAA | sha256sum` outputs `c34ab6abb7b2bb595bc25c3b388c872fd1d575819a8f55cc689510285e212385`.
* 34 down. 440Hz is an "A" note. 7 pulses would be AAAAAAA
* 38 down. Eggs can be [https://www.saudereggs.com/blog/egg-grading-system/ "graded on a veriety if aspects"], with grades B, A, or AA. Eggs with a reasonably firm yolk are graded A, so having halve a dozen of them gives you AAAAAA eggs.
* 39 down. A [https://en.wikipedia.org/wiki/Multi-tap "multitap keyboard"] is a text entry system for mobile phones. Most numbers are associated with three letters, and tapping the same number multiple times in rapid succession selects the 1st, 2nd, or 3rd number. 2 is "a", 22 is "b", 222 is "c", 3 is "d", etc. 2-2-2-2-2-2 translates to "aaaaaa"
* 40 down. .- is Morse Code for A. It reads out as AAAAAA
* Hint: If you ever encounter this puzzle in a crossword app, just [ Type A ]

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

[A crossword puzzle image, with the following clues:]

:Across
:1. Famous Pvt. Wilhelm quote
:11. IPv6 address record
:15. "CIPHERTEXT" decrypted with Vigenère key "CIPHERTEXT"
:16. 8mm diameter battery
:17. "Warthog" attack aircraft
:18. Every third letter in the word for "inability to visualize"
:19. An acrostic hidden on the first page of the dictionary
:21. Default paper size in Europe
:22. First four unary strings
:23. Lysine codon
:24. 40 CFR Part 63 subpart concerning asphalt pollution
:25. Top bond credit rating
:26. Audi coupe
:27. A pair of small remote batteries, when inserted
:29. Unofficial Howard Dean slogan
:32. A 4.0 report card
:33. The "Harlem Globetrotters of baseball" (vowels only)
:34. 2018 Kiefer song
:35. Top Minor League tier
:36. Reply elicited by a dentist
:38. ANAA's airport
:41. Macaulay Culkin's review of aftershave
:43. Marketing agency trade grp.
:44. Soaring climax of Linda Elder's ''Man of La Mancha''
:46. Military flight commuinity org.
:47. Iconic line from Tarzan
:48. Every other letter of Jimmy Wales's birth state
:49. Warthog'd postscript after "They call me ''mister'' pig!"
:50. Message to Elsa in ''Frozen 2''
:51. Lola, when betting it all on Black 20 in ''Run Lola Run''
:Down
:1. Game featuring "a reckless disregard for gravity"
:2. 101010101010101010101010 base 2-> base 16
:3. Google phone released July '22
:4. It's five times better than that ''other'' steak sauce
:5. ToHex(43690)
:6. Freddie Mercury lyric from ''Under Pressure''
:7. Full-size Audi luxury sedan
:8. Fast path through a multiple choice marketing survey
:9. 12356631 in base 26
:10. Viral Jimmy Barnes chorus
:11. Ruby Rhod catchphrase
:12. badbeef + 9efcebbb
:13. In Wet Let's ''Ur Mum'', what the singer has been practicing
:14. Refrain from Nora Reed bot
:20. Mario button presses to ascend Minas Tirith's walls
:24. Vermont historic route north from Bennington
:26. High-budget video game
:28. Unotrhodox Tic-Tac-Toe win
:29. String whose SHA-256 hash ends "...689510285e212385"
:30. Arnold's remark to the Predator
:31. The vowels in the fire salamander's binomial name
:32. Janet Leigh ''Psycho'' line
:34. Seven 440Hz pulses
:37. Audi luxury sports sedan
:38. A half-dozen eggs with reasonably firm yolks
:39. 2-2-2-2-2-2 on a multitap phone keypad
:40. .- .- .- .- .- .-
:42. Rating for China's best tourist attractions
:43. Standard drumstick size
:45. "The rain/in Spain/falls main-/ly on the plain" rhyme scheme

{{comic discussion}}

2956: Number Line Branch

2024-07-09T02:27:24Z

Blue in real life: explained number

{{comic
| number = 2956
| date = July 8, 2024
| title = Number Line Branch
| image = number_line_branch_2x.png
| imagesize = 469x235px
| noexpand = true
| titletext = Attention all passengers: This is an express sequence to infinity. If your stop is not a power of two, please disembark now.
}}

==Explanation==
{{incomplete|Created by a SECOND BOT TO REDUCE CONGESTION - Please change this comment when editing this page. Do NOT delete this tag too soon.}}
This comic likens the {{w|number line}} to a line of a railroad or subway system. These often have branches where different trains continue on to a different destination, with different stops along the way. In the number line, one branch (presumably the original) contains ordinary numbers, while the newly opened branch consists of some completely different numbers, denoted with different symbols as an analogue to those we use as digits. The branches seems to split at π.

The symbols seen are:
* a rectangle, representing thrembo,
* a vertical bar with two perpendicular "prongs" to the right, like a {{w|double turnstile}},
* a vertical bar topped by a circle bisected by it, like some versions of a lowercase phi,
* a spiral, and
* a triangle, like an uppercase delta.
Some of these symbols are already used elsewhere in mathematics.

The sequence ending with a bold mark at Δ (whereas the original number line fades out) suggests that it is the end of this branching sequence. Mathematicians, apparently, could only afford to construct 5 additional numbers, or their research hasn't yet found other numbers.

The title text makes a parallel between a train stopping at a station and a numerical sequence "stopping" at a number – that is, taking it as a value. It's a spoof of announcements that are typically made on trains, so that riders can confirm that they're on a train that goes to their desired station; an "express train" typically makes fewer stops so it can reach its final destination sooner. In this case, the express train only stops at powers of 2; presumably the "local" stops at every integer, so the travel time will be exponentially longer. Either way, the number line extends to infinity, so it will take forever to get to the final destination.

A fictional number was previously shown in [[899: Number Line]] ("gird"), and fictional ''numerals'' were shown in [[2206: Mavis Beacon]]. And similar treatment of mathematics as public infrastructure was seen in [[2735: Coordinate Plane Closure]].

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
:[The number line for natural numbers, going from 0 to 10 and trailing off, with a marker at 0 to indicate that it is the start of the sequence. At about 3.125, the line branches off into a second line, which contains five odd-looking symbols, and stops at the fifth one.]
:Caption: Good news! After thousands of years, mathematicians have finally opened a second branch on the number line to reduce congestion.

{{comic discussion}}

[[Category:Math]]

2950: Situation

2024-06-24T19:05:49Z

Blue in real life: removed indent

{{comic
| number = 2950
| date = June 24, 2024
| title = Situation
| image = situation_2x.png
| imagesize = 578x306px
| noexpand = true
| titletext = We're right under the flight path for the scheduled orbital launch, but don't worry--it's too cold out for the rockets to operate safely, so I'm sure they'll postpone.
}}

==Explanation==
{{incomplete|Created by a Shark, the iceberg of the sea - Please change this comment when editing this page. Do NOT delete this tag too soon.}}
In this comic, we see an "unsinkable ship" (a name given to the Titanic) attached to the Hindenburg, which blew up because of the hydrogen filled environment in 1937. The Hindenburg is described as a "hydrogen-filled airship for iceberg spotting", referring to how the Titanic sank. To the right of the airship we see the Chernobyl reactor (or the "Soviet-Era nuclear reactor undergoing a turbine test"). During its turbine test, the reactors exploded, sending plumes of radioactive material into the air. On the right side of the comic, there is a "bridge prone to aeroelastic flutter in high winds", referring to the Tacoma Narrows bridge collapse. These events together had a cumulative death count of around 1700 people. All of these disasters can be studied as failures of engineering, so all 5 in one place would make engineers extremely nervous.
The title text refers to the Challenger Explosion, and how the primary and secondary O-rings meant to prevent a leakage of hot gases were incapable of properly sealing the gaps between the SRB joints due to the launch happening during extremely cold weather, when it should have been postponed.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

[An airship flying, labelled] Hydrogen-filled scout airship for iceberg spotting
[The airship is chained to a ship, going along a river, labelled] Unsinkable ocean liner

[In the background on the coast a nuclear power plant, labelled] Soviet-era nuclear reactor undergoing a turbine test
[The boat and airship are steering towards a bridge, labelled] Bridge prone to aeroelastic flutter in high winds

[Caption]
In retrospect, we should have noticed how nervous the situation was making the engineers.

{{comic discussion}}

2950: Situation

2024-06-24T19:05:35Z

Blue in real life: bit of elaboration

2655: Asking Scientists Questions

2024-05-01T18:17:50Z

Blue in real life:

{{comic
| number = 2655
| date = August 5, 2022
| title = Asking Scientists Questions
| image = asking_scientists_questions.png
| titletext = 'Does the substance feel weird to the touch?' is equally likely to get the answers 'Don't be ridiculous, you would never put your hand near a sample. We have safety protocols.' and 'Yeah, and it tastes AWFUL.'
}}

==Explanation==
Answering the questions in [[Randall]]'s [[what if? (blog)|''what if?'' blog]] and his books ''[[What If? (book)|What If?]]'' and ''[[What If? 2]]'' requires a wide variety of scientific expertise, much of which he is unfamiliar with. To make up for this deficiency, Randall (here represented by [[Cueball]]) asks other scientists for help, in this comic represented by [[Hairbun]].

Normal people (not from the scientific community) have certain expectations about scientists, as they would any group of people {{Citation needed}}. In the case of scientists, they are often expected to be overly serious, "measuring the marigolds" rather than enjoying the simpler or more subjective things in life. This is reflected in the first panel, where Hairbun gets annoyed by Cueball's "frivolous scenario" and wants to work on formulas instead. This is the scenario one would have expected from the standard assumptions regarding scientists.

In reality, scientists are just like regular people in most respects (as has been represented before in xkcd) and this is why Randall, in reality, is more likely to experience something like what is shown in the second panel. Here Hairbun is quite pleased to get "something fun to think about" as part of their work, instead of filling out her grant applications.

Grants are donations of money from private or government organizations specifically aimed to fund scientific experiments and projects; in many fields, they are the most common source of funding, and the vast majority of scientists not directly employed by private industry rely on grants to support their work. These organizations require applicants to provide detailed information on the goal of the project, the methodology, the expected results, the specific uses to which the money will be put, and more. Applying for a grant is thus a lengthy, painstaking process that more often than not results in disappointment since most granting agencies have only enough money to approve a small percentage of applications. It also has little to do directly with the actual science the scientists want to perform. Thus most scientists find it a necessary but time-consuming and unpleasant part of their job, and the one here expresses relief at taking a break from this part of their work.

Hairbun then asks if Cueball would like to fill out grant applications, trying to bribe him with coauthor credit, powerful magnets, and plutonium. Co-authorship on scientific papers helps scientists advance in the "{{w|publish or perish}}" world of academic careers; such co-authorship might be above-board, if Cueball contributed scientific ideas while helping write grant applications, or it might not. Plutonium is used in making atomic bombs and is thus a tightly controlled substance, as well as being {{w|Plutonium#Toxicity|highly toxic}} due to both its radioactivity and its heavy metal poison effects. The scientist is so relieved to have found someone who might take over filling out grant applications that they are willing to give them access to such a dangerous material without even knowing their name.

The title text notes that not all responses were complaints about grant applications, noting two kinds of answers to the question "Does the substance feel weird to the touch?" which Randall claims are equally common. The first is the sort of response you would expect from a stereotypical scientist, just noting safety procedures that are common with such a substance and how they impede attempts to determine how weird a substance feels. The second is "Yeah, and it tastes AWFUL," implying that the scientist in question has not only touched the weird substance, but also tasted it. It could have been carelessness of some kind, perhaps having touched their mouth after handling a sample, but it might have been from deliberately licking it or even putting it in their mouth. Whatever the reason they tasted it, they are enthusiastically volunteering this elaboration without any actual prompting.

Eating a bizarre substance is likely a bad idea,{{Citation needed}} as it could be poisonous. Less toxic minerals such as halite are sometimes [http://www.galleries.com/minerals/property/taste.htm evaluated based on taste] as an informal test of their composition; nearly every mineral of low toxicity (and some otherwise) has been tasted for science. However, this is self-evidently a bad idea if you're not sure whether a mineral is a non-toxic one or a similar-looking toxic mineral; mineral taste-tests should only be performed by experts who know they're not eating arsenic or stibnite.

==Transcript==
:[There is a light gray caption written above two normal text captions that are above two panels:]
:For the last few years, I've been working on answering peoples' ridiculous questions for ''What If? 2'', which sometimes meant asking scientists for help.

:[Caption above the left panel:]
:How you'd expect scientists to respond to ridiculous questions:

:[Cueball, representing Randall, stands holding a pad and pencil in front of a desk. There are a stack of three books and some papers on the desk. Hairbun is sitting on an office chair behind the desk. She is pointing at Cueball.]
:Hairbun: Why would you present me with this frivolous scenario?
:Hairbun: Such an absurd query can serve no practical purpose.
:Hairbun: Now go; you distract me from my formulas.

:[Caption above the right panel:]
:How they actually respond:

:[Same setting as in the left panel but the items on the desk have changed, so there are now a laptop computer and a stack with a book and some papers on the desk. Hairbun is sitting on an office chair behind the desk. She is holding another stack of papers up in both hands.]
:Hairbun: Oh thank God, something fun to think about that's not grant applications.
:Hairbun: Hey, do '''''you''''' want to fill out some grant applications? I'll give you literally anything. Coauthor credit. Powerful magnets. Do you want plutonium? I can get you plutonium.
:Hairbun: What was your name again?

:[Light gray caption below the panels:]
:To see the answers I found, preorder at xkcd.com/whatif2 (out 9/13)

{{comic discussion}}

[[Category:Book promotion]]
[[Category:Comics featuring Randall Munroe]]
[[Category:Comics featuring Hairbun]]
[[Category:Science]]
[[Category:Comics with lowercase text]]
[[Category:What If?]]

2926: Doppler Effect

2024-04-29T20:04:27Z

Blue in real life:

{{comic
| number = 2926
| date = April 29, 2024
| title = Doppler Effect
| image = doppler_effect_2x.png
| imagesize = 671x317px
| noexpand = true
| titletext = The Doppler effect is a mysterious wavelength-shifting phenomenon which seems to primarily affect sirens, which is why the 🚨 emoji is red.
}}

==Explanation==
{{incomplete|Created by an ALARMED BOT THAT GOES... - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

[[Miss Lenhart]] is teaching a class about the concept of {{w|redshift}} and using the {{w|Doppler effect}} as a demonstration. The comparison begins as relevant, but then quickly becomes extraneous when she brings up the "BUTTON THAT MAKES IT GO PYEEW! PYEEW!". In fact, it seems she cares more about her special interest in various emergency vehicle sirens than about astronomy, the field in which she teaches.

In the second and third panels, Miss Lenhart talks about the strange noise sirens (and cars) make when the pass you. The usual explanation of Doppler effect is that the source of the sound waves is moving. Consider a sound being generated at a frequency of 1000 cycles per second (Hertz); each wave will propagate at a fixed speed in the air, the speed of sound. The car generates peak A, which begins moving away at the speed of sound, and 1/1000th of a second later, generates peak B, which also begins moving away at the speed of sound. In that 1/1000th of a second between peaks being generated, the car has traveled slightly forward, so peak B is produced slightly farther along the car's direction of travel than the previous peak. For an observer in front of the car, because peak B was generated a bit closer to the observer, they would measure (hear) a shorter wavelength (higher pitch) than if the peaks were generated from a stationary car. Similarly, for an observer behind the car, because peak B was generated a bit further away, they would hear a lower pitch. However, Miss Lenhart doesn't make this usual explanation and instead starts talking about how cool sirens are.

Redshift is the same concept applied to wavelength of light and stellar objects. Red has longer wavelength than blue, and stars gets red when they move away from us and blue when they move towards us. We usually talk about redshift and not blueshift because while stars in our galaxy can move in any direction, the other galaxies are all moving away from us, and in fact they are moving quicker the father away they are, due to universe expanding. Note that unlike the usual explanation of redshift for sirens, a major component the red shift of light from distant galaxies is due to the expansion of space the light passing through while the light is in transit, rather than just the relative motion of the source and observer. This effect is not an important component of the Doppler shift for sirens.

The title text explains that the Doppler effect particularly affects sirens. This isn't actually true,{{cn}} but it may seem like it because sirens are almost always the analogy given, as in Miss Lenhart's lecture. Then it claims that the emoji for sirens is red because they're associated with redshift. Actually, the emoji is a picture of the rotating light on top of emergency vehicles; these tend to be used in conjunction with sirens, and they're red because this color typically signifies danger or warning.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

:[Miss Lenhart is pointing with a stick to a whiteboard with various scientific drawings and words, including but not only a graph.]
:Miss Lenhart: The more distant a galaxy is, the redder its light.
:Miss Lenhart: Why? Well, that's an interesting question.

:[Zoom in on Miss Lenhart.]
:Miss Lenhart: Ever notice how, when a siren is approaching, it sounds like ''Bweeeeeeeeee''...

:[Zoom in on Miss Lenhart with her arms raised.]
:Miss Lenhart: ...but then it zooms past and goes ''Nyeeeeooooowww?''
:Miss Lenhart: And sometimes they hit a button that makes it go ''Pyeew! Pyeew!'' really loud?

:[Miss Lenhart with her finger raised is standing in front of the whiteboard and holding the stick down.]
:Miss Lenhart: And in Europe they go ''Ooooeeeeooooeeee...''
:Off-panel voice: So ''why'' are galaxies red?
:Miss Lenhart: Oh, no idea.
:Miss Lenhart: Anyway, another siren I like is...

{{comic discussion}}

[[Category:Comics featuring Miss Lenhart]]
[[Category:Physics]]

2916: Machine

2024-04-26T22:24:53Z

Blue in real life: Undo revision 340622 by 172.69.34.165 (talk)

{{comic
| number = 2916
| date = April 5, 2024
| title = Machine
| image = machine_2x.png
| imagesize = 740x740px
| noexpand = true
| titletext = The Credible Machine
}}
* To experience the interactivity, visit the [https://xkcd.com/2916/ original comic].

==Explanation==
{{incomplete|Created by a WELL OILED ROBOT. Do NOT delete this tag too soon.}}
This interactive game is the 14th [[:Category:April fools' comics|April fools' comic]] released by [[Randall]]. The previous April fools' comic was [[2765: Escape Speed]] from 2023, which was released on Wednesday, April 19, 2023. "Machine" has been updated multiple times in the weeks following its release, adding the following features:
* the trophy and shot glass props
* the cat, which swats balls in front of it
* the inanimate cat and bunny decorations
* a system of links, which encodes the XY coordinates of the currently viewed cell, and the time (i.e. the entire machine's state after a certain moderation action)
* a button to follow a nearby ball as it traverses through the machine, also preventing it from despawning

As referenced in the title text, this game is a spiritual successor to the 1990s and early 2000s PC puzzle game series {{w|The Incredible Machine}}, a game Randall played as a kid. Both games have several objects in common:
* fan
* cat
* ramps
* balls of varying densities

The comic starts in a main screen where the user can create a {{w|Rube Goldberg machine}} in a "Cell" where the goal is to route a constant stream of colored balls from inputs on the ceiling or walls to outputs of matching colors on the walls or floor. After the comic is first opened a window pops up over the machine where Cueball in a lab coat tells you to route the balls from the inputs to the outputs. A button opens a “tool panel” where there are large and small boards available for use, as well as some gimmicky stuff like prisms (which deflect marbles) and fans (which blow marbles around), plus decorative elements which have no effect on the balls.

Typically, inputs and outputs only accept balls of a single color. However, some outputs accept multiple colors, indicated by a double arrow, and some inputs produce multiple colors. When the player is designing their 'machine', this will involve multiple full streams merged into one (supplied by a double-exit on the adjacent submission). Machines now working in the full grid may, however, find that their sources now contain stray balls of other types that were not handled properly, but there is no way to force a re-edit of the machine to alter its behavior to account for this.

If any balls are left in your cell for more than 30 seconds, they fade away. The first time a ball fades away another popup informs you that the balls are removed for security reasons. An indicator next to each exit increases for each ball of the correct color that passes through an exit, and reduces when no balls pass through, or if balls of the wrong color pass through it. While that exit is not properly supplied it displays a red cross, which changes to a green tick when a sufficient, and sufficiently clean, stream of balls is supplied. The first time you have built a machine which succeeds in routing enough balls of the correct color to ''all'' relevant outputs, a popup will prompt you to submit your cell to be added to the public machine. (Subsequently, the submit button will quietly change from 'inactive' (pale) to clickable (dark). This will change back again if any ball transfers dip back below the required threshold for any reason, such as further editing or an end to a 'fluke' glut of accumulated balls.)

Choosing to submit your cell will give you a textbox to give this cell a name. Proceeding through that, you will now see your cell within the 'grid' and a 'live' feed of balls from any relevant neighboring cells (which may be more sporadic then the feed you designed your cell with, and contain stray balls of different types). If any supplying-neighbors are still marked as "under construction", they ''may'' provide the balls as if perfectly routed from their own (eventual) source, but will eventually dry up. If your newly submitted creation is placed in the lowest row of cells, balls will be dispensed through the exit at the bottom, but there will be no launcher to propel them towards the pit, and they will vanish as they leave the exit.

Upon reopening the link to this comic without coordinate and time parameters, your recently created machine will most likely not be visible in the space you built it in. [https://www.reddit.com/user/xzaphenia/comments/ Reddit user xzaphenia] has claimed on r/xkcd that this is because there is a moderation team (of which they are a member) and that [https://www.reddit.com/r/xkcd/comments/1c1ixmb/comment/kzc3rmg/ the main page only shows public, approved machines]. This team of people, including those credited as co-creators of this comic, select machines according to their preferences (and little to no formal criteria besides [https://www.reddit.com/r/xkcd/comments/1c0sp60/comment/kz6hbgl/ coolness, innovativeness, effectiveness], and [https://www.reddit.com/r/xkcd/comments/1c0bsk2/comment/kyvfean/ privacy concerns]). Given the number of 'bottom-layer' cells that are likely primed ready to be completed (e.g. the grid-width of twelve, perhaps staggered across adjacent rows) and the many possible worldwide contributors at any one time, it may be that the chances of being picked for permanence is low; and certainly would have been lower early on in the comic's existence during the initial frantic rush to participate. [https://www.reddit.com/r/xkcd/comments/1c0sp60/comment/kz6hbgl/ It is also claimed that at some point, moderation will be cut off and the machine will be considered "complete"].

<gallery heights="200" widths="150">
File:2916_popup_intro.png|Introduction popup
File:2916_popup_time.png|Time limit popup
File:2916_popup_submit.png|Submission popup
</gallery>

The button in the bottom right corner allows you to toggle between editing your own machine and a page where you can drag around to view all of the machines that have been submitted and accepted, with a title for each in the upper left corner. In this view you can see that all of the outputs are also inputs for another cell, except for the top row where the inputs come from off screen and the lowest row which output through a launcher of some kind to a set of four colored-coded containers far below. Any empty cells are marked off by yellow tape with the words "UNDER CONSTRUCTION" as well as "DJIA ↑ 31415" once in each cell. "DJIA" stands for the Dow Jones Industrial Average, with "DJIA ↑ 31415" indicating that it rose to 31415 points, 31415 being the first five digits of pi, without the period. This would often be displayed on a yellow 'ticker', which might look superficially similar to the yellow barrier tape.

When viewing the whole machine, a button in the bottom left corner, added later, allows you to follow the path of the nearest ball as it passes from cell to cell. This will also make the ball you are following immortal - not subject to the 30s timeout rule. Another later addition was a button in the top left corner which copies a URL that will take you directly to the current cell that you are viewing. However, the link that is created will always show you the version of the machine at the time that you were viewing it, without any subsequent additions.

Whenever balls reach the bottom of the grid, they are directed towards four containers, one of each color. Most balls are accurately sent to their appropriate container, though there are some misfires. These containers are above a pit, and periodically dump their contents. Balls in the pit are subject to a 90 second culling rule, unlike the balls in the cells above. If no balls are directed towards the containers, the pit will be empty. If one or two streams of balls are making it, Cueball and Megan sit in a small boat named the USS Buoyancy, and when sufficient balls are being deposited, the boat begins to float and move. More streams of balls are likely to add more changes. Balls which miss or overspill the pit fall out of the bottom of the frame.

Under construction cells will feed balls of the appropriate color into neighboring cells so long as you are not looking at them. Once you scroll to look at them, the supply of balls stops and subsequent cells in the chain will not receive any; scroll away from them again and the supply will resume.

The grid is 12 cells wide, and grows in height. The largest size observed so far is 12x85, for a total of 1020 cells. The machine's height is determined by the lowest cell; This can be either your submitted cell, or a cell created by another user.

Imperfections in the machines (whether accidental or by design) and the impossibility of entirely avoiding collisions when crossing streams inevitably lead to significant levels of losses and pollution with the wrong color balls. Indeed, using the follow ball function appears to demonstrate that it is quite rare for a ball to survive more than several machines without getting stuck somewhere. This should mean that effectively no balls would reach the lower layers. This implies that there is some 'creative accounting' going on to ensure that cells lower in the grid still have balls to process - simulating flow only for a few nearby cells, while assuming that those cells themselves have pure, steady inputs.

There is a hard limit of 100 items (both physically interactive and purely decorative) that can be placed in any given arena. If you have placed 75 items, a count will appear in the component bar of your piece-count ("''##''/100"), which will go away again if you delete items to bring it below this count. The count text turns red at "100/100", at which point no more items can be added, only existing ones moved (or removed, to lower the count again).

===Toolbox items===
{| class="wikitable" style="margin:auto"
|+ List of objects
|-
! Description !! Effect !! Image
|-
| Plank || Static obstacle || [[File:2916_plank.png|frameless|upright=0.25]]
|-
| Hammer || Static obstacle || [[File:2916_hammer.png|frameless|upright=0.25]]
|-
| Sword || Static obstacle || [[File:2916_sword.png|frameless|upright=0.25]]
|-
| Hinged scoop&dagger; || Rotates around its hinge, tries to stay horizontal with a springy effect || [[File:2916_scoop.png|frameless|upright=0.25]] [[File:2916_scoop_mirrored.png|frameless|upright=0.25]]
|-
| Anvil || Static obstacle || [[File:2916_anvil.png|frameless|upright=0.125]]
|-
| Brick || Static obstacle || [[File:2916_brick.png|frameless|upright=0.125]]
|-
| Fan || Blows away balls in front of it. Different colors are affected by differing amounts (yellow balls are lightest, and can be levitated above an upward-facing fan).|| [[File:2916_fan.png|frameless|upright=0.125]]
|-
| Pillow || Balls will not bounce if they hit it || [[File:2916_pillow.png|frameless|upright=0.125]]
|-
| Bumper || Bounces balls away at significantly higher speed || [[File:2916_round_bumper.png|frameless|upright=0.125]] [[File:2916_bumper_left.png|frameless|upright=0.125]] [[File:2916_bumper_right.png|frameless|upright=0.125]]
|-
| Attractor/Black Hole* || Pulls balls toward center || [[File:2916_attractor.png|frameless|upright=0.125]]
|-
| Repulsor/White hole* || Repels balls away from center || [[File:2916_repulsor.png|frameless|upright=0.125]]
|-
| Prism || "Refracts" and internally-reflects balls as they otherwise pass through the object, the color of the ball ''may'' cause them to react (as much as possible) according to the respective color across the element. || [[File:2916_prism.png|frameless|upright=0.125]]
|-
| Wheel&Dagger; || Spins, deflects balls, can jam with enough resistance (e.g. glut of balls or against other elements). || [[File:2916_wheel.png|frameless|upright=0.125]]
|-
| "Good job" trophy || Static obstacle || [[File:2916_trophy.png|frameless|upright=0.125]]
|-
| Glass cup || Static obstacle. Container, with a nominal capacity of up to four balls (in whole or in part) within it. || [[File:2916_cup.png|frameless|upright=0.125]]
|-
| Cat || Swats away balls in front of itself (was added later) || [[File:2916_cat_new.png|frameless|upright=0.25]]
|-
! colspan="3" style="text-align:center" | Non-physical items
|-
| Right-facing Ponytail, with raised arms || Intangible decoration || [[File:2916_ponytail_arms.png|frameless|upright=0.125]]
|-
| Right-facing Ponytail, standing || Intangible decoration || [[File:2916_ponytail.png|frameless|upright=0.125]]
|-
| Left-facing Cueball, with raised arms || Intangible decoration || [[File:2916_cueball_arms.png|frameless|upright=0.125]]
|-
| Left-facing White Hat, standing || Intangible decoration || [[File:2916_whitehat.png|frameless|upright=0.125]]
|-
| Rightwards-facing Knit Cap, in an 'action' pose || Intangible decoration || [[File:2916_knitcap_resting.png|frameless|upright=0.25]]
|-
| Right-facing Knit Cap, standing || Intangible decoration || [[File:2916_knitcap.png|frameless|upright=0.125]]
|-
| Helmet-wearing figure, standing || Intangible decoration || [[File:2916_helmet.png|frameless|upright=0.125]]
|-
| Squirrel || Intangible decoration || [[File:2916_squirrel.png|frameless|upright=0.125]]
|-
| "Probably Deterministic" sign || Intangible decoration || [[File:2916_deterministic.png|frameless|upright=0.25]]
|-
| [[1682: Bun|Bun]] || Intangible decoration || [[File:2916_rabbit.png|frameless|upright=0.125]]
|-
| Cat || Intangible decoration || [[File:2916_cat.png|frameless|upright=0.125]]
|}

:<nowiki/>* — The Attractor and Repulsor are omnidirectional, but the area of effect can be resized to extend or restrict its influence. You do this by way of its bounding box with corner and mid-edged 'drag nodes' and a circular area that shows the current extent, which are only visible when the element is actively selected. This resize can be no larger than will make the box/circle touch the edges, no smaller than the fixed graphic and will always be identically proportioned in both axes.

:&dagger; — The hinged scoops are strictly horizontal, on building. They will rotate away from and (spring back to) horizontal according to interactions with balls or other non-decorative items that may be placed to disturb their balance, sometimes with further interesting interactions (that may or may not be intentional or useful). There are two selectable versions of this item. (The only ''other'' object class with a clear (and practical) asymmetry, for which a mirrored chirality can be chosen from the sidebar, are the two versions of triangular "Bonk"-bumpers.)

:&Dagger; — The wheel is an actively rotating element that starts off, by default, spinning anticlockwise. Pressing or tapping left/right arrow keys, when a placed wheel is selected, will adjust that wheel's rotation rate to be more/less anticlockwise. Adjusting it beyond zero rotation allows you to make it spin in the opposite direction.
:Rotation can be increased well beyond the point at which the {{w|wagon-wheel effect}} occurs, which may make it difficult to work out the spin direction of an overspeed wheel element (and thus which arrow keys will slow or speed up its rotation, if you have forgotten), though observing its impact upon any balls that strike it ''should'' make its current spin-direction obvious.
:The 'bounding editing box' will usually appear rotated, possibly according to the spinning graphic's current orientation upon selection, but remains at that (often non-orthagonal) angle even as the wheel spins (if it can) during this period of selection for editing.

All other items can be manually re-angled by a 'loop node' arm extending from the bounding box. If you cannot see the 'angle node' for such a selected item, which is normally at the top of any freshly placed item but follows any re-angling that may have already applied, it could be that you have placed the item too close to the edge in which direction the node extends. To rotate it, move the object away from the edge to access the construction node (after which, you can drag the object back if required – but see below).

Rotation may be limited by the {{w|minimum bounding box}} that is the 'selection box', this is not necessarily the more flush {{w|convex hull}} of the collision-map built into the graphic. Should a corner of the bounding box need to move across the edge of the build-area, it will do nothing more than touch the edge until there is sufficient angle-drag to snap it to the angle from which that corner now comes back away from the edge; or, when it has a long straight edge currently flush with the edge boundary, it may snap to exactly 180°, in rotation, whereupon the opposite long straight edge is flush to the construction area edge. All objects that are drag-moved, similarly, cannot be moved any further than their current bounding box touching the construction-area edging. The bounding box for the rotating wheel is a notable exception to this, being not under any direct angle-control by the player. Instead, it seems to use the bounding inscribed circle that defines the wheel edge iteslf.

Apart from some interactions between the hinged scoops and any element (including other hinged scoops), there is no preventative 'collision detection' between objects during user-placement, which may overlap/cover each other (the most recently spawned item graphically overlays any earlier one). The wheel object will only spin if not constrained by other physical elements (including the spokes of an adjacent wheel, not in counter-rotation) but can still be dragged and placed anywhere within the boundary of the construction area.

The continuous stream(s) of balls respect all ''tangible'' objects, which includes any currently being dragged/rotated, though may prematurely vanish if forced between two items moved to touch/overlap each other. It is possible to to indirectly nudge balls by carefully moving a tangible object's surface into them (or holding them within it, e.g. the "cup"). This may be useful for rescuing temporarily stray balls (before they time-out anyway), unjamming an area with a construction-induced glut ''or'' for testing a ball-path that is not currently being fed 'naturally'. Doing so ''can'' then conceivably fulfil all the exit-gate requirements (temporarily), as it might also transiently spoil some required routing, but the manual intervention will not be possible once a 'machine' has been submit.

===Non-player items===

Ball containers at the bottom of the machine
{|
|[[File:2916_container_red.png|thumb|center|50px]]
|[[File:2916_container_yellow.png|thumb|center|50px]]
|[[File:2916_container_blue.png|thumb|center|50px]]
|[[File:2916_container_green.png|thumb|center|50px]]
|}

Cueball and Megan in the ''USS Buoyancy''
[[File:4d425c.png|thumb|left|150px]]
 

Pit below the ''USS Buoyancy'' (not to scale)
[[File:2916_pit_bottom.png|thumb|left|300px]]
 

=== Color routing ===
The different ball colors have different physical properties. Red balls are more bouncy than other balls, green balls are heavier, and yellow balls are lighter and slightly bouncy. The following values were extracted from the code:
{| class="wikitable sortable"
! Color
! Mass
! Density
! Restitution (bounciness)
! Linear damping (drag)
|-
! data-sort-key="00F" | Blue
| 0.08
| 1
| 0
| 0
|-
! data-sort-key="F00" | Red
| 0.08
| 1
| 0.8
| 0
|-
! data-sort-key="0F0" | Green
| 0.75
| 9.325
| 0
| 0
|-
! data-sort-key="FF0" | Yellow
| 0.024
| 0.3
| 0.6
| 2
|}

For certain combinations of inlet and outlet 'gates', it is necessary to 'cross the streams'. e.g. to direct righthand-entry balls to a lefthand-exit and vice-versa. It is possible to just construct the field to send two (or more!) sets of balls to fly across a common gap, to land on an appropriate reception area that leads to the chosen exit. But, though this is not {{w|Proton pack#Crossing the streams|completely inadvised}}, the timing of the balls cannot be guaranteed to be in sync (or, rather, anti-sync) with each other and collisions ''will'' occur, especially under the variations of delivery that might significantly alter the ballistic path across the gap. Even if the trial machine works, in isolation with a steady stream of all balls entering the field of play, once submitted it will inevitably be fed by a more chaotically-routed preceeding construction.

In order to maintain sufficient correct arrivals at exits, it may be necessary to add a method of filtering the hues.

This could just mean introducing a 'wrong hue trap' beyond any crossing point(s) that send the occasionally wrong ball back to the cross point (or let them time-out in a dead-end, relying upon few enough failures from the rest of the balls, along with all colliding balls that subsequently missed ''any'' chance of reaching an exit). Alternatively, two (or more) feeds of marbles could be fed through a deliberate 'sorter' that does a sufficiently reasonable job of separating the combined sets out towards their intended target-exits.

The various physical qualities of the balls suggest a number of methods for redirecting separate hues to separate onward journeys. This can be done by isolating a hue from every other hue, then passing on (if necessary) to a setup extracting a different one from the remainder, and perhaps also a third time. It may also be possible to merge 'arrangements' of sorting mechanics to efficiently distribute straight into three ''or even four'' onward tracks towards the desired outputs, but that is left as an exercise to the reader.


{| class="wikitable"
! style="background-color:black; color:white" | To separate !! style="background-color:lightblue" | Blue !! style="background-color:lightgreen" | Green !! style="background-color:yellow" | Yellow !! style="background-color:red" | Red
|-
! style="background-color:red" | Red
| *R/B* | '''Use 'bounce''''
The sole difference is how much balls will rebound from objects. Well managed and constrained ricochets should allow a sorting action.
| *R/G* | '''Use mass or 'bounce''''
Green balls cannot be levitated by a vertical fan. An incline across any such fan(s) will levitate only non-Greens. Green, like Blue, rebounds differently to Red. Green balls are also affected by black holes much less than all other balls.
| *R/Y* | ''See Y/B''
| *R/R* style="text-align: center; background-color:black; color:white" | n/a
|-
! style="background-color:yellow" | Yellow
| *Y/B* | '''All methods'''
Yellow, alone, exhibits high drag against any unforced motion. It is also unique in all other ways; e.g. can be levitated highest, against all other hues (though most profoundly against Green).
| *Y/G* | ''See Y/B''
| *Y/Y* style="text-align: center; background-color:black; color:white" | n/a
| *Y/R* style="text-align: center; background-color:gray" | ''See Y/B'' 
|-
! style="background-color:lightgreen" | Green
| *G/B* | '''Use mass'''
Green balls cannot be levitated by a vertical fan. There is also a not so marginal difference in density that might be exploited, such as by using black holes, which only minimally effects Green (perhaps showing an effective difference between mass of attraction and mass of inertia).
| *G/G* style="text-align: center; background-color:black; color:white" | n/a
| *G/Y* style="text-align: center; background-color:gray" | ''See Y/B'' 
| *G/R* style="text-align: center; background-color:gray" | See R/G
|-
! style="background-color:lightblue" | Blue
| *B/B* style="text-align: center; background-color:black; color:white" | n/a
| *B/G* style="text-align: center; background-color:gray" | See G/B
| *B/Y* style="text-align: center; background-color:gray" | See Y/B
| *B/R* style="text-align: center; background-color:gray" | See R/B
|}

Even when not strictly necessary for one's own submission, once submitted into the full playing grid the player's own contribution may find itself working with less 'pure' delivered ball-streams (from an imperfectly separating feed-in contribution). It is possible that this more interactive disruption can make the new setup behave erratically or even entirely incorrectly.

It might be thought good practice (but not ''necessary'') to deliberately combine any or all inputs and do a full job of splitting them again, just in anticipation of possibly having to deal with such cross-contamination and being able to 'clean up' the onward stream(s) for the benefit of others. This would of course be particularly difficult if the isolated building-phase does not provide all four hues to 'test' against, so any speculatively added filtering would have to be added 'blind' (and only on the offchance that any anticipated incorrect balls will actually enter the arena) and without any legitimate exits to which such rejects could be shunted (therefore could accumulate, up until any 'time out' that might apply to any ball once operational as part of the combined grid).

Single-input/single-output designs might not particularly require ''any'' sorting mechanism, in theory, though the unexpected 'contamination' of the system with balls of different masses/etc could perhaps introduce malfunctioning passage from the added chaos it might succumb to.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

:[The placeholder image shows four balls, colored red, green, yellow and blue, bouncing on top of three white blocks. Text in the center: "[visit xkcd.com to view]"]

:[Cueball with lab coat, intro popup]
:Cueball: Balls falling into your cell should be routed to the outputs at a steady rate.

:[Cueball with lab coat, warning popup]
:Cueball: For security reasons, balls that remain in your device for more than 30 seconds will be removed and destroyed.

:[Cueball with lab coat, submit popup]
:Cueball: Congratulations! Your contraption has passed all tests. Press [submit button] to submit it to be added to the machine!

==Trivia==
Once again an April Fool's Day Comic came out late, as Randall did not release this on April 1st, even though April 1st did fall on a Monday, a normal release day. It first came four days later with the Friday release on April 5th. That this is to be considered an April fools' comic, in spite of the later release, was confirmed on the xkcd Facebook page.

*Randall acknowledges the people who helped him create this comic in a [[Header_text#Machine|comic-specific header text]].
**With 11 different involved apart from Randall this is by far the comic with most people involved.
*Some hidden keyboard shortcuts have been found:
** Follow balls: Ctrl + Alt/Option + B (now also accessible by using the button provided)
** Show debug overlay: Ctrl + Shift + Win/Cmd + D
*** This may particularly clash with browser functionality, e.g. Firefox's "New Bookmarks" dialogue which will need closing, though still activating the overlay graphics.
** Delete selected item: Delete (Fn + Delete on Mac)
*When Randall posted a [https://www.facebook.com/TheXKCD/posts/pfbid0Cs97awQZi1ZiaEXouAex9tXrwAS3qJV3RmAiuCq5uvZQwqZVMgDmcqJ7JU9LYodYl link to this comic] on his [https://www.facebook.com/TheXKCD Facebook feed], he directly wrote that it was a late April Fools' Day!
**MACHINE
**Happy Belated April Fool's Day!
**This thus ends any discussion of whether this should be seen as an April Fool's comic or not.
**It just came out 4 days late. This has also happened several times since [[Garden]].
[[File:2916 Machine Facebook April fools' confirmation.png]]

{{comic discussion}}

[[Category:April fools' comics]]
[[Category:Comics with color]]
[[Category:Dynamic comics]]
[[Category:Comics with animation]]
[[Category:Interactive comics]]
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Megan]]
[[Category:Comics featuring Ponytail]]
[[Category:Comics featuring White Hat]]
[[Category:Comics featuring Knit Cap]]
[[Category:Characters with hats]]
[[Category:Squirrels]]
[[Category:Buns]]
[[Category:Cats]]

2916: Machine

2024-04-17T00:04:14Z

Blue in real life: another update

{{comic
| number = 2916
| date = April 5, 2024
| title = Machine
| image = machine_2x.png
| imagesize = 740x740px
| noexpand = true
| titletext = The Credible Machine
}}
* To experience the interactivity, visit the [https://xkcd.com/2916/ original comic].

==Explanation==
{{incomplete|Created by a WELL OILED ROBOT. Do NOT delete this tag too soon.}}
This interactive game is the 14th [[:Category:April fools' comics|April fools' comic]] released by [[Randall]]. The previous April fools' comic was [[2765: Escape Speed]] from 2023, which was released on Wednesday, April 19, 2023. "Machine" has been updated multiple times in the weeks following its release, adding the following features:
* the trophy and shot glass props
* the cat, which swats balls in front of it
* the inanimate cat and bunny decorations
* a system of links, which encodes the XY coordinates of the currently viewed cell, and the time (i.e. the entire machine's state after a certain moderation action)
* a button to follow a nearby ball as it traverses through the machine, also preventing it from despawning

As referenced in the title text, this game is a spiritual successor to the 1990s and early 2000s PC puzzle game series {{w|The Incredible Machine}}, a game Randall played as a kid. Both games have several objects in common:
* fan
* cat
* ramps
* balls of varying densities

The comic starts in a main screen where the user can create a {{w|Rube Goldberg machine}} in a "Cell" where the goal is to route a constant stream of colored balls from inputs on the ceiling or walls to outputs of matching colors on the walls or floor. After the comic is first opened a window pops up over the machine where Cueball in a lab coat tells you to route the balls from the inputs to the outputs. A button opens a “tool panel” where there are large and small boards available for use, as well as some gimmicky stuff like prisms (which deflect marbles) and fans (which blow marbles around), plus decorative elements which have no effect on the balls.

Typically, inputs and outputs only accept balls of a single color. However, some outputs accept multiple colors, indicated by a double arrow, and some inputs produce multiple colors. When the player is designing their 'machine', this will involve multiple full streams merged into one (supplied by a double-exit on the adjacent submission). Machines now working in the full grid may, however, find that their sources now contain stray balls of other types that were not handled properly, but there is no way to force a re-edit of the machine to alter its behavior to account for this.

If any balls are left in your cell for more than 30 seconds, they fade away. The first time a ball fades away another popup informs you that the balls are removed for security reasons. An indicator next to each exit increases for each ball of the correct color that passes through an exit, and reduces when no balls pass through, or if balls of the wrong color pass through it. While that exit is not properly supplied it displays a red cross, which changes to a green tick when a sufficient, and sufficiently clean, stream of balls is supplied. The first time you have built a machine which succeeds in routing enough balls of the correct color to ''all'' relevant outputs, a popup will prompt you to submit your cell to be added to the public machine. (Subsequently, the submit button will quietly change from 'inactive' (pale) to clickable (dark). This will change back again if any ball transfers dip back below the required threshold for any reason, such as further editing or an end to a 'fluke' glut of accumulated balls.)

Choosing to submit your cell will give you a textbox to give this cell a name. Proceeding through that, you will now see your cell within the 'grid' and a 'live' feed of balls from any relevant neighboring cells (which may be more sporadic then the feed you designed your cell with, and contain stray balls of different types). If any supplying-neighbors are still marked as "under construction", they ''may'' provide the balls as if perfectly routed from their own (eventual) source, but will eventually dry up. If your newly submitted creation is placed in the lowest row of cells, balls will be dispensed through the exit at the bottom, but there will be no launcher to propel them towards the pit, and they will vanish as they leave the exit.

Upon reopening the link to this comic without coordinate and time parameters, your recently created machine will most likely not be visible in the space you built it in. [https://www.reddit.com/user/xzaphenia/comments/ Reddit user xzaphenia] has claimed on r/xkcd that this is because there is a moderation team (of which they are a member) and that [https://www.reddit.com/r/xkcd/comments/1c1ixmb/comment/kzc3rmg/ the main page only shows public, approved machines]. This team of people, including those credited as co-creators of this comic, select machines according to their preferences (and little to no formal criteria besides [https://www.reddit.com/r/xkcd/comments/1c0sp60/comment/kz6hbgl/ coolness, innovativeness, effectiveness], and [https://www.reddit.com/r/xkcd/comments/1c0bsk2/comment/kyvfean/ privacy concerns]). Given the number of 'bottom-layer' cells that are likely primed ready to be completed (e.g. the grid-width of twelve, perhaps staggered across adjacent rows) and the many possible worldwide contributors at any one time, it may be that the chances of being picked for permanence is low; and certainly would have been lower early on in the comic's existence during the initial frantic rush to participate. [https://www.reddit.com/r/xkcd/comments/1c0sp60/comment/kz6hbgl/ It is also claimed that at some point, moderation will be cut off and the machine will be considered "complete"].

<gallery heights="200" widths="150">
File:2916_popup_intro.png|Introduction popup
File:2916_popup_time.png|Time limit popup
File:2916_popup_submit.png|Submission popup
</gallery>

The button in the bottom right corner allows you to toggle between editing your own machine and a page where you can drag around to view all of the machines that have been submitted and accepted, with a title for each in the upper left corner. In this view you can see that all of the outputs are also inputs for another cell, except for the top row where the inputs come from off screen and the lowest row which output through a launcher of some kind to a set of four colored-coded containers far below. Any empty cells are marked off by yellow tape with the words "UNDER CONSTRUCTION" as well as "DJIA ↑ 31415" once in each cell. "DJIA" stands for the Dow Jones Industrial Average, with "DJIA ↑ 31415" indicating that it rose to 31415 points, 31415 being the first five digits of pi, without the period. This would often be displayed on a yellow 'ticker', which might look superficially similar to the yellow barrier tape.

When viewing the whole machine, a button in the bottom left corner, added later, allows you to follow the path of the nearest ball as it passes from cell to cell. This will also make the ball you are following immortal - not subject to the 30s timeout rule. Another later addition was a button in the top left corner which copies a URL that will take you directly to the current cell that you are viewing. However, the link that is created will always show you the version of the machine at the time that you were viewing it, without any subsequent additions.

Whenever balls reach the bottom of the grid, they are directed towards four containers, one of each color. Most balls are accurately sent to their appropriate container, though there are some misfires. These containers are above a pit, and periodically dump their contents. Balls in the pit are subject to the same 30s culling rule as balls in the cells above. If no balls are directed towards the containers, the pit will be empty. If one or two streams of balls are making it, Cueball and Megan sit in a small boat named the USS Buoyancy, and when sufficient balls are being deposited, the boat begins to float and move. More streams of balls are likely to add more changes. Balls which miss or overspill the pit fall out of the bottom of the frame.

Under construction cells will feed balls of the appropriate color into neighboring cells so long as you are not looking at them. Once you scroll to look at them, the supply of balls stops and subsequent cells in the chain will not receive any; scroll away from them again and the supply will resume.

The grid is 12 cells wide, and grows in height. The largest size observed so far is 12x65, for a total of 780 cells. The machine's height is determined by the lowest cell; This can be either your submitted cell, or a cell created by another user.

Imperfections in the machines (whether accidental or by design) and the impossibility of entirely avoiding collisions when crossing streams inevitably lead to significant levels of losses and pollution with the wrong color balls. Indeed, using the follow ball function appears to demonstrate that it is quite rare for a ball to survive more than several machines without getting stuck somewhere. This should mean that effectively no balls would reach the lower layers. This implies that there is some 'creative accounting' going on to ensure that cells lower in the grid still have balls to process - simulating flow only for a few nearby cells, while assuming that those cells themselves have pure, steady inputs.

There is a hard limit of 100 items (both physically interactive and purely decorative) that can be placed in any given arena. If you have placed 75 items, a count will appear in the component bar of your piece-count ("''##''/100"), which will go away again if you delete items to bring it below this count. The count text turns red at "100/100", at which point no more items can be added, only existing ones moved (or removed, to lower the count again).

===Toolbox items===
{| class="wikitable" style="margin:auto"
|+ List of objects
|-
! Description !! Effect !! Image
|-
| Plank || Static obstacle || [[File:2916_plank.png|frameless|upright=0.25]]
|-
| Hammer || Static obstacle || [[File:2916_hammer.png|frameless|upright=0.25]]
|-
| Sword || Static obstacle || [[File:2916_sword.png|frameless|upright=0.25]]
|-
| Hinged scoop&dagger; || Rotates around its hinge, tries to stay horizontal with a springy effect || [[File:2916_scoop.png|frameless|upright=0.25]] [[File:2916_scoop_mirrored.png|frameless|upright=0.25]]
|-
| Anvil || Static obstacle || [[File:2916_anvil.png|frameless|upright=0.125]]
|-
| Brick || Static obstacle || [[File:2916_brick.png|frameless|upright=0.125]]
|-
| Fan || Blows away balls in front of it. Different colors are affected by differing amounts (yellow balls are lightest, and can be levitated above an upward-facing fan).|| [[File:2916_fan.png|frameless|upright=0.125]]
|-
| Pillow || Balls will not bounce if they hit it || [[File:2916_pillow.png|frameless|upright=0.125]]
|-
| Bumper || Bounces balls away at significantly higher speed || [[File:2916_round_bumper.png|frameless|upright=0.125]] [[File:2916_bumper_left.png|frameless|upright=0.125]] [[File:2916_bumper_right.png|frameless|upright=0.125]]
|-
| Attractor/Black Hole* || Pulls balls toward center || [[File:2916_attractor.png|frameless|upright=0.125]]
|-
| Repulsor/White hole* || Repels balls away from center || [[File:2916_repulsor.png|frameless|upright=0.125]]
|-
| Prism || "Refracts" and internally-reflects balls as they otherwise pass through the object, the color of the ball ''may'' cause them to react (as much as possible) according to the respective color across the element. || [[File:2916_prism.png|frameless|upright=0.125]]
|-
| Wheel&Dagger; || Spins, deflects balls, can jam with enough resistance (e.g. glut of balls or against other elements). || [[File:2916_wheel.png|frameless|upright=0.125]]
|-
| "Good job" trophy || Static obstacle || [[File:2916_trophy.png|frameless|upright=0.125]]
|-
| Glass cup || Static obstacle. Container, with a nominal capacity of up to four balls (in whole or in part) within it. || [[File:2916_cup.png|frameless|upright=0.125]]
|-
| Cat || Swats away balls in front of itself (was added later) || [[File:2916_cat_new.png|frameless|upright=0.25]]
|-
! colspan="3" style="text-align:center" | Non-physical items
|-
| Right-facing Ponytail, with raised arms || Intangible decoration || [[File:2916_ponytail_arms.png|frameless|upright=0.125]]
|-
| Right-facing Ponytail, standing || Intangible decoration || [[File:2916_ponytail.png|frameless|upright=0.125]]
|-
| Left-facing Cueball, with raised arms || Intangible decoration || [[File:2916_cueball_arms.png|frameless|upright=0.125]]
|-
| Left-facing White Hat, standing || Intangible decoration || [[File:2916_whitehat.png|frameless|upright=0.125]]
|-
| Rightwards-facing Knit Cap, in an 'action' pose || Intangible decoration || [[File:2916_knitcap_resting.png|frameless|upright=0.25]]
|-
| Right-facing Knit Cap, standing || Intangible decoration || [[File:2916_knitcap.png|frameless|upright=0.125]]
|-
| Helmet-wearing figure, standing || Intangible decoration || [[File:2916_helmet.png|frameless|upright=0.125]]
|-
| Squirrel || Intangible decoration || [[File:2916_squirrel.png|frameless|upright=0.125]]
|-
| "Probably Deterministic" sign || Intangible decoration || [[File:2916_deterministic.png|frameless|upright=0.25]]
|-
| [[1682: Bun|Bun]] || Intangible decoration || [[File:2916_rabbit.png|frameless|upright=0.125]]
|-
| Cat || Intangible decoration || [[File:2916_cat.png|frameless|upright=0.125]]
|}

:<nowiki/>* — The Attractor and Repulsor are omnidirectional, but the area of effect can be resized to extend or restrict its influence. You do this by way of its bounding box with corner and mid-edged 'drag nodes' and a circular area that shows the current extent, which are only visible when the element is actively selected. This resize can be no larger than will make the box/circle touch the edges, no smaller than the fixed graphic and will always be identically proportioned in both axes.

:&dagger; — The hinged scoops are strictly horizontal, on building. They will rotate away from and (spring back to) horizontal according to interactions with balls or other non-decorative items that may be placed to disturb their balance, sometimes with further interesting interactions (that may or may not be intentional or useful). There are two selectable versions of this item. (The only ''other'' object class with a clear (and practical) asymmetry, for which a mirrored chirality can be chosen from the sidebar, are the two versions of triangular "Bonk"-bumpers.)

:&Dagger; — The wheel is an actively rotating element that starts off, by default, spinning anticlockwise. Pressing or tapping left/right arrow keys, when a placed wheel is selected, will adjust that wheel's rotation rate to be more/less anticlockwise. Adjusting it beyond zero rotation allows you to make it spin in the opposite direction.
:Rotation can be increased well beyond the point at which the {{w|wagon-wheel effect}} occurs, which may make it difficult to work out the spin direction of an overspeed wheel element (and thus which arrow keys will slow or speed up its rotation, if you have forgotten), though observing its impact upon any balls that strike it ''should'' make its current spin-direction obvious.
:The 'bounding editing box' will usually appear rotated, possibly according to the spinning graphic's current orientation upon selection, but remains at that (often non-orthagonal) angle even as the wheel spins (if it can) during this period of selection for editing.

All other items can be manually re-angled by a 'loop node' arm extending from the bounding box. If you cannot see the 'angle node' for such a selected item, which is normally at the top of any freshly placed item but follows any re-angling that may have already applied, it could be that you have placed the item too close to the edge in which direction the node extends. To rotate it, move the object away from the edge to access the construction node (after which, you can drag the object back if required – but see below).

Rotation may be limited by the {{w|minimum bounding box}} that is the 'selection box', this is not necessarily the more flush {{w|convex hull}} of the collision-map built into the graphic. Should a corner of the bounding box need to move across the edge of the build-area, it will do nothing more than touch the edge until there is sufficient angle-drag to snap it to the angle from which that corner now comes back away from the edge; or, when it has a long straight edge currently flush with the edge boundary, it may snap to exactly 180°, in rotation, whereupon the opposite long straight edge is flush to the construction area edge. All objects that are drag-moved, similarly, cannot be moved any further than their current bounding box touching the construction-area edging. The bounding box for the rotating wheel is a notable exception to this, being not under any direct angle-control by the player. Instead, it seems to use the bounding inscribed circle that defines the wheel edge iteslf.

Apart from some interactions between the hinged scoops and any element (including other hinged scoops), there is no preventative 'collision detection' between objects during user-placement, which may overlap/cover each other (the most recently spawned item graphically overlays any earlier one). The wheel object will only spin if not constrained by other physical elements (including the spokes of an adjacent wheel, not in counter-rotation) but can still be dragged and placed anywhere within the boundary of the construction area.

The continuous stream(s) of balls respect all ''tangible'' objects, which includes any currently being dragged/rotated, though may prematurely vanish if forced between two items moved to touch/overlap each other. It is possible to to indirectly nudge balls by carefully moving a tangible object's surface into them (or holding them within it, e.g. the "cup"). This may be useful for rescuing temporarily stray balls (before they time-out anyway), unjamming an area with a construction-induced glut ''or'' for testing a ball-path that is not currently being fed 'naturally'. Doing so ''can'' then conceivably fulfil all the exit-gate requirements (temporarily), as it might also transiently spoil some required routing, but the manual intervention will not be possible once a 'machine' has been submit.

===Non-player items===

Ball containers at the bottom of the machine
{|
|[[File:2916_container_red.png|thumb|center|50px]]
|[[File:2916_container_yellow.png|thumb|center|50px]]
|[[File:2916_container_blue.png|thumb|center|50px]]
|[[File:2916_container_green.png|thumb|center|50px]]
|}

Cueball and Megan in the ''USS Buoyancy''
[[File:4d425c.png|thumb|left|150px]]
 

Pit below the ''USS Buoyancy'' (not to scale)
[[File:2916_pit_bottom.png|thumb|left|300px]]
 

=== Color routing ===
The different ball colors have different physical properties. Red balls are more bouncy than other balls, green balls are heavier, and yellow balls are lighter and slightly bouncy. The following values were extracted from the code:
{| class="wikitable sortable"
! Color
! Mass
! Density
! Restitution (bounciness)
! Linear damping (drag)
|-
! data-sort-key="00F" | Blue
| 0.08
| 1
| 0
| 0
|-
! data-sort-key="F00" | Red
| 0.08
| 1
| 0.8
| 0
|-
! data-sort-key="0F0" | Green
| 0.75
| 9.325
| 0
| 0
|-
! data-sort-key="FF0" | Yellow
| 0.024
| 0.3
| 0.6
| 2
|}

For certain combinations of inlet and outlet 'gates', it is necessary to 'cross the streams'. e.g. to direct righthand-entry balls to a lefthand-exit and vice-versa. It is possible to just construct the field to send two (or more!) sets of balls to fly across a common gap, to land on an appropriate reception area that leads to the chosen exit. But, though this is not {{w|Proton pack#Crossing the streams|completely inadvised}}, the timing of the balls cannot be guaranteed to be in sync (or, rather, anti-sync) with each other and collisions ''will'' occur, especially under the variations of delivery that might significantly alter the ballistic path across the gap. Even if the trial machine works, in isolation with a steady stream of all balls entering the field of play, once submitted it will inevitably be fed by a more chaotically-routed preceeding construction.

In order to maintain sufficient correct arrivals at exits, it may be necessary to add a method of filtering the hues.

This could just mean introducing a 'wrong hue trap' beyond any crossing point(s) that send the occasionally wrong ball back to the cross point (or let them time-out in a dead-end, relying upon few enough failures from the rest of the balls, along with all colliding balls that subsequently missed ''any'' chance of reaching an exit). Alternatively, two (or more) feeds of marbles could be fed through a deliberate 'sorter' that does a sufficiently reasonable job of separating the combined sets out towards their intended target-exits.

The various physical qualities of the balls suggest a number of methods for redirecting separate hues to separate onward journeys. This can be done by isolating a hue from every other hue, then passing on (if necessary) to a setup extracting a different one from the remainder, and perhaps also a third time. It may also be possible to merge 'arrangements' of sorting mechanics to efficiently distribute straight into three ''or even four'' onward tracks towards the desired outputs, but that is left as an exercise to the reader.


{| class="wikitable"
! style="background-color:black; color:white" | To separate !! style="background-color:lightblue" | Blue !! style="background-color:lightgreen" | Green !! style="background-color:yellow" | Yellow !! style="background-color:red" | Red
|-
! style="background-color:red" | Red
| *R/B* | '''Use 'bounce''''
The sole difference is how much balls will rebound from objects. Well managed and constrained ricochets should allow a sorting action.
| *R/G* | '''Use mass or 'bounce''''
Green balls cannot be levitated by a vertical fan. An incline across any such fan(s) will levitate only non-Greens. Green, like Blue, rebounds differently to Red. Green balls are also affected by black holes much less than all other balls.
| *R/Y* | ''See Y/B''
| *R/R* style="text-align: center; background-color:black; color:white" | n/a
|-
! style="background-color:yellow" | Yellow
| *Y/B* | '''All methods'''
Yellow, alone, exhibits high drag against any unforced motion. It is also unique in all other ways; e.g. can be levitated highest, against all other hues (though most profoundly against Green).
| *Y/G* | ''See Y/B''
| *Y/Y* style="text-align: center; background-color:black; color:white" | n/a
| *Y/R* style="text-align: center; background-color:gray" | ''See Y/B'' 
|-
! style="background-color:lightgreen" | Green
| *G/B* | '''Use mass'''
Green balls cannot be levitated by a vertical fan. There is also a not so marginal difference in density that might be exploited, such as by using black holes, which only minimally effects Green (perhaps showing an effective difference between mass of attraction and mass of inertia).
| *G/G* style="text-align: center; background-color:black; color:white" | n/a
| *G/Y* style="text-align: center; background-color:gray" | ''See Y/B'' 
| *G/R* style="text-align: center; background-color:gray" | See R/G
|-
! style="background-color:lightblue" | Blue
| *B/B* style="text-align: center; background-color:black; color:white" | n/a
| *B/G* style="text-align: center; background-color:gray" | See G/B
| *B/Y* style="text-align: center; background-color:gray" | See Y/B
| *B/R* style="text-align: center; background-color:gray" | See R/B
|}

Even when not strictly necessary for one's own submission, once submitted into the full playing grid the player's own contribution may find itself working with less 'pure' delivered ball-streams (from an imperfectly separating feed-in contribution). It is possible that this more interactive disruption can make the new setup behave erratically or even entirely incorrectly.

It might be thought good practice (but not ''necessary'') to deliberately combine any or all inputs and do a full job of splitting them again, just in anticipation of possibly having to deal with such cross-contamination and being able to 'clean up' the onward stream(s) for the benefit of others. This would of course be particularly difficult if the isolated building-phase does not provide all four hues to 'test' against, so any speculatively added filtering would have to be added 'blind' (and only on the offchance that any anticipated incorrect balls will actually enter the arena) and without any legitimate exits to which such rejects could be shunted (therefore could accumulate, up until any 'time out' that might apply to any ball once operational as part of the combined grid).

Single-input/single-output designs might not particularly require ''any'' sorting mechanism, in theory, though the unexpected 'contamination' of the system with balls of different masses/etc could perhaps introduce malfunctioning passage from the added chaos it might succumb to.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

:[The placeholder image shows four balls, colored red, green, yellow and blue, bouncing on top of three white blocks. Text in the center: "[visit xkcd.com to view]"]

:[Cueball with lab coat, intro popup]
:Cueball: Balls falling into your cell should be routed to the outputs at a steady rate.

:[Cueball with lab coat, warning popup]
:Cueball: For security reasons, balls that remain in your device for more than 30 seconds will be removed and destroyed.

:[Cueball with lab coat, submit popup]
:Cueball: Congratulations! Your contraption has passed all tests. Press [submit button] to submit it to be added to the machine!

==Trivia==
Once again an April Fool's Day Comic came out late, as Randall did not release this on April 1st, even though April 1st did fall on a Monday, a normal release day. It first came four days later with the Friday release on April 5th. That this is to be considered an April fools' comic, in spite of the later release, was confirmed on the xkcd Facebook page.

*Randall acknowledges the people who helped him create this comic in a [[Header_text#Machine|comic-specific header text]].
**With 11 different involved apart from Randall this is by far the comic with most people involved.
*Some hidden keyboard shortcuts have been found:
** Follow balls: Ctrl + Alt/Option + B (now also accessible by using the button provided)
** Show debug overlay: Ctrl + Shift + Win/Cmd + D
*** This may particularly clash with browser functionality, e.g. Firefox's "New Bookmarks" dialogue which will need closing, though still activating the overlay graphics.
** Delete selected item: Delete (Fn + Delete on Mac)
*When Randall posted a [https://www.facebook.com/TheXKCD/posts/pfbid0Cs97awQZi1ZiaEXouAex9tXrwAS3qJV3RmAiuCq5uvZQwqZVMgDmcqJ7JU9LYodYl link to this comic] on his [https://www.facebook.com/TheXKCD Facebook feed], he directly wrote that it was a late April Fools' Day!
**MACHINE
**Happy Belated April Fool's Day!
**This thus ends any discussion of whether this should be seen as an April Fool's comic or not.
**It just came out 4 days late. This has also happened several times since [[Garden]].
[[File:2916 Machine Facebook April fools' confirmation.png]]

{{comic discussion}}

[[Category:April fools' comics]]
[[Category:Comics with color]]
[[Category:Dynamic comics]]
[[Category:Comics with animation]]
[[Category:Interactive comics]]
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Megan]]
[[Category:Comics featuring Ponytail]]
[[Category:Comics featuring White Hat]]
[[Category:Comics featuring Knit Cap]]
[[Category:Characters with hats]]
[[Category:Squirrels]]
[[Category:Buns]]
[[Category:Cats]]

2916: Machine

2024-04-17T00:00:24Z

Blue in real life: new information on moderation

{{comic
| number = 2916
| date = April 5, 2024
| title = Machine
| image = machine_2x.png
| imagesize = 740x740px
| noexpand = true
| titletext = The Credible Machine
}}
* To experience the interactivity, visit the [https://xkcd.com/2916/ original comic].

==Explanation==
{{incomplete|Created by a WELL OILED ROBOT. Do NOT delete this tag too soon.}}
This interactive game is the 14th [[:Category:April fools' comics|April fools' comic]] released by [[Randall]]. The previous April fools' comic was [[2765: Escape Speed]] from 2023, which was released on Wednesday, April 19, 2023. "Machine" has been updated multiple times in the weeks following its release, adding the following features:
* the trophy and shot glass props
* the cat, which swats balls in front of it
* the inanimate cat and bunny decorations
* the system of links, which encodes the XY coordinates of the currently viewed cell, and the time (i.e. the entire machine's state after a certain moderation action)

As referenced in the title text, this game is a spiritual successor to the 1990s and early 2000s PC puzzle game series {{w|The Incredible Machine}}, a game Randall played as a kid. Both games have several objects in common:
* fan
* cat
* ramps
* balls of varying densities

The comic starts in a main screen where the user can create a {{w|Rube Goldberg machine}} in a "Cell" where the goal is to route a constant stream of colored balls from inputs on the ceiling or walls to outputs of matching colors on the walls or floor. After the comic is first opened a window pops up over the machine where Cueball in a lab coat tells you to route the balls from the inputs to the outputs. A button opens a “tool panel” where there are large and small boards available for use, as well as some gimmicky stuff like prisms (which deflect marbles) and fans (which blow marbles around), plus decorative elements which have no effect on the balls.

Typically, inputs and outputs only accept balls of a single color. However, some outputs accept multiple colors, indicated by a double arrow, and some inputs produce multiple colors. When the player is designing their 'machine', this will involve multiple full streams merged into one (supplied by a double-exit on the adjacent submission). Machines now working in the full grid may, however, find that their sources now contain stray balls of other types that were not handled properly, but there is no way to force a re-edit of the machine to alter its behavior to account for this.

If any balls are left in your cell for more than 30 seconds, they fade away. The first time a ball fades away another popup informs you that the balls are removed for security reasons. An indicator next to each exit increases for each ball of the correct color that passes through an exit, and reduces when no balls pass through, or if balls of the wrong color pass through it. While that exit is not properly supplied it displays a red cross, which changes to a green tick when a sufficient, and sufficiently clean, stream of balls is supplied. The first time you have built a machine which succeeds in routing enough balls of the correct color to ''all'' relevant outputs, a popup will prompt you to submit your cell to be added to the public machine. (Subsequently, the submit button will quietly change from 'inactive' (pale) to clickable (dark). This will change back again if any ball transfers dip back below the required threshold for any reason, such as further editing or an end to a 'fluke' glut of accumulated balls.)

Choosing to submit your cell will give you a textbox to give this cell a name. Proceeding through that, you will now see your cell within the 'grid' and a 'live' feed of balls from any relevant neighboring cells (which may be more sporadic then the feed you designed your cell with, and contain stray balls of different types). If any supplying-neighbors are still marked as "under construction", they ''may'' provide the balls as if perfectly routed from their own (eventual) source, but will eventually dry up. If your newly submitted creation is placed in the lowest row of cells, balls will be dispensed through the exit at the bottom, but there will be no launcher to propel them towards the pit, and they will vanish as they leave the exit.

Upon reopening the link to this comic without coordinate and time parameters, your recently created machine will most likely not be visible in the space you built it in. [https://www.reddit.com/user/xzaphenia/comments/ Reddit user xzaphenia] has claimed on r/xkcd that this is because there is a moderation team (of which they are a member) and that [https://www.reddit.com/r/xkcd/comments/1c1ixmb/comment/kzc3rmg/ the main page only shows public, approved machines]. This team of people, including those credited as co-creators of this comic, select machines according to their preferences (and little to no formal criteria besides [https://www.reddit.com/r/xkcd/comments/1c0sp60/comment/kz6hbgl/ coolness, innovativeness, effectiveness], and [https://www.reddit.com/r/xkcd/comments/1c0bsk2/comment/kyvfean/ privacy concerns]). Given the number of 'bottom-layer' cells that are likely primed ready to be completed (e.g. the grid-width of twelve, perhaps staggered across adjacent rows) and the many possible worldwide contributors at any one time, it may be that the chances of being picked for permanence is low; and certainly would have been lower early on in the comic's existence during the initial frantic rush to participate. [https://www.reddit.com/r/xkcd/comments/1c0sp60/comment/kz6hbgl/ It is also claimed that at some point, moderation will be cut off and the machine will be considered "complete"].

<gallery heights="200" widths="150">
File:2916_popup_intro.png|Introduction popup
File:2916_popup_time.png|Time limit popup
File:2916_popup_submit.png|Submission popup
</gallery>

The button in the bottom right corner allows you to toggle between editing your own machine and a page where you can drag around to view all of the machines that have been submitted and accepted, with a title for each in the upper left corner. In this view you can see that all of the outputs are also inputs for another cell, except for the top row where the inputs come from off screen and the lowest row which output through a launcher of some kind to a set of four colored-coded containers far below. Any empty cells are marked off by yellow tape with the words "UNDER CONSTRUCTION" as well as "DJIA ↑ 31415" once in each cell. "DJIA" stands for the Dow Jones Industrial Average, with "DJIA ↑ 31415" indicating that it rose to 31415 points, 31415 being the first five digits of pi, without the period. This would often be displayed on a yellow 'ticker', which might look superficially similar to the yellow barrier tape.

When viewing the whole machine, a button in the bottom left corner, added later, allows you to follow the path of the nearest ball as it passes from cell to cell. This will also make the ball you are following immortal - not subject to the 30s timeout rule. Another later addition was a button in the top left corner which copies a URL that will take you directly to the current cell that you are viewing. However, the link that is created will always show you the version of the machine at the time that you were viewing it, without any subsequent additions.

Whenever balls reach the bottom of the grid, they are directed towards four containers, one of each color. Most balls are accurately sent to their appropriate container, though there are some misfires. These containers are above a pit, and periodically dump their contents. Balls in the pit are subject to the same 30s culling rule as balls in the cells above. If no balls are directed towards the containers, the pit will be empty. If one or two streams of balls are making it, Cueball and Megan sit in a small boat named the USS Buoyancy, and when sufficient balls are being deposited, the boat begins to float and move. More streams of balls are likely to add more changes. Balls which miss or overspill the pit fall out of the bottom of the frame.

Under construction cells will feed balls of the appropriate color into neighboring cells so long as you are not looking at them. Once you scroll to look at them, the supply of balls stops and subsequent cells in the chain will not receive any; scroll away from them again and the supply will resume.

The grid is 12 cells wide, and grows in height. The largest size observed so far is 12x65, for a total of 780 cells. The machine's height is determined by the lowest cell; This can be either your submitted cell, or a cell created by another user.

Imperfections in the machines (whether accidental or by design) and the impossibility of entirely avoiding collisions when crossing streams inevitably lead to significant levels of losses and pollution with the wrong color balls. Indeed, using the follow ball function appears to demonstrate that it is quite rare for a ball to survive more than several machines without getting stuck somewhere. This should mean that effectively no balls would reach the lower layers. This implies that there is some 'creative accounting' going on to ensure that cells lower in the grid still have balls to process - simulating flow only for a few nearby cells, while assuming that those cells themselves have pure, steady inputs.

There is a hard limit of 100 items (both physically interactive and purely decorative) that can be placed in any given arena. If you have placed 75 items, a count will appear in the component bar of your piece-count ("''##''/100"), which will go away again if you delete items to bring it below this count. The count text turns red at "100/100", at which point no more items can be added, only existing ones moved (or removed, to lower the count again).

===Toolbox items===
{| class="wikitable" style="margin:auto"
|+ List of objects
|-
! Description !! Effect !! Image
|-
| Plank || Static obstacle || [[File:2916_plank.png|frameless|upright=0.25]]
|-
| Hammer || Static obstacle || [[File:2916_hammer.png|frameless|upright=0.25]]
|-
| Sword || Static obstacle || [[File:2916_sword.png|frameless|upright=0.25]]
|-
| Hinged scoop&dagger; || Rotates around its hinge, tries to stay horizontal with a springy effect || [[File:2916_scoop.png|frameless|upright=0.25]] [[File:2916_scoop_mirrored.png|frameless|upright=0.25]]
|-
| Anvil || Static obstacle || [[File:2916_anvil.png|frameless|upright=0.125]]
|-
| Brick || Static obstacle || [[File:2916_brick.png|frameless|upright=0.125]]
|-
| Fan || Blows away balls in front of it. Different colors are affected by differing amounts (yellow balls are lightest, and can be levitated above an upward-facing fan).|| [[File:2916_fan.png|frameless|upright=0.125]]
|-
| Pillow || Balls will not bounce if they hit it || [[File:2916_pillow.png|frameless|upright=0.125]]
|-
| Bumper || Bounces balls away at significantly higher speed || [[File:2916_round_bumper.png|frameless|upright=0.125]] [[File:2916_bumper_left.png|frameless|upright=0.125]] [[File:2916_bumper_right.png|frameless|upright=0.125]]
|-
| Attractor/Black Hole* || Pulls balls toward center || [[File:2916_attractor.png|frameless|upright=0.125]]
|-
| Repulsor/White hole* || Repels balls away from center || [[File:2916_repulsor.png|frameless|upright=0.125]]
|-
| Prism || "Refracts" and internally-reflects balls as they otherwise pass through the object, the color of the ball ''may'' cause them to react (as much as possible) according to the respective color across the element. || [[File:2916_prism.png|frameless|upright=0.125]]
|-
| Wheel&Dagger; || Spins, deflects balls, can jam with enough resistance (e.g. glut of balls or against other elements). || [[File:2916_wheel.png|frameless|upright=0.125]]
|-
| "Good job" trophy || Static obstacle || [[File:2916_trophy.png|frameless|upright=0.125]]
|-
| Glass cup || Static obstacle. Container, with a nominal capacity of up to four balls (in whole or in part) within it. || [[File:2916_cup.png|frameless|upright=0.125]]
|-
| Cat || Swats away balls in front of itself (was added later) || [[File:2916_cat_new.png|frameless|upright=0.25]]
|-
! colspan="3" style="text-align:center" | Non-physical items
|-
| Right-facing Ponytail, with raised arms || Intangible decoration || [[File:2916_ponytail_arms.png|frameless|upright=0.125]]
|-
| Right-facing Ponytail, standing || Intangible decoration || [[File:2916_ponytail.png|frameless|upright=0.125]]
|-
| Left-facing Cueball, with raised arms || Intangible decoration || [[File:2916_cueball_arms.png|frameless|upright=0.125]]
|-
| Left-facing White Hat, standing || Intangible decoration || [[File:2916_whitehat.png|frameless|upright=0.125]]
|-
| Rightwards-facing Knit Cap, in an 'action' pose || Intangible decoration || [[File:2916_knitcap_resting.png|frameless|upright=0.25]]
|-
| Right-facing Knit Cap, standing || Intangible decoration || [[File:2916_knitcap.png|frameless|upright=0.125]]
|-
| Helmet-wearing figure, standing || Intangible decoration || [[File:2916_helmet.png|frameless|upright=0.125]]
|-
| Squirrel || Intangible decoration || [[File:2916_squirrel.png|frameless|upright=0.125]]
|-
| "Probably Deterministic" sign || Intangible decoration || [[File:2916_deterministic.png|frameless|upright=0.25]]
|-
| [[1682: Bun|Bun]] || Intangible decoration || [[File:2916_rabbit.png|frameless|upright=0.125]]
|-
| Cat || Intangible decoration || [[File:2916_cat.png|frameless|upright=0.125]]
|}

:<nowiki/>* — The Attractor and Repulsor are omnidirectional, but the area of effect can be resized to extend or restrict its influence. You do this by way of its bounding box with corner and mid-edged 'drag nodes' and a circular area that shows the current extent, which are only visible when the element is actively selected. This resize can be no larger than will make the box/circle touch the edges, no smaller than the fixed graphic and will always be identically proportioned in both axes.

:&dagger; — The hinged scoops are strictly horizontal, on building. They will rotate away from and (spring back to) horizontal according to interactions with balls or other non-decorative items that may be placed to disturb their balance, sometimes with further interesting interactions (that may or may not be intentional or useful). There are two selectable versions of this item. (The only ''other'' object class with a clear (and practical) asymmetry, for which a mirrored chirality can be chosen from the sidebar, are the two versions of triangular "Bonk"-bumpers.)

:&Dagger; — The wheel is an actively rotating element that starts off, by default, spinning anticlockwise. Pressing or tapping left/right arrow keys, when a placed wheel is selected, will adjust that wheel's rotation rate to be more/less anticlockwise. Adjusting it beyond zero rotation allows you to make it spin in the opposite direction.
:Rotation can be increased well beyond the point at which the {{w|wagon-wheel effect}} occurs, which may make it difficult to work out the spin direction of an overspeed wheel element (and thus which arrow keys will slow or speed up its rotation, if you have forgotten), though observing its impact upon any balls that strike it ''should'' make its current spin-direction obvious.
:The 'bounding editing box' will usually appear rotated, possibly according to the spinning graphic's current orientation upon selection, but remains at that (often non-orthagonal) angle even as the wheel spins (if it can) during this period of selection for editing.

All other items can be manually re-angled by a 'loop node' arm extending from the bounding box. If you cannot see the 'angle node' for such a selected item, which is normally at the top of any freshly placed item but follows any re-angling that may have already applied, it could be that you have placed the item too close to the edge in which direction the node extends. To rotate it, move the object away from the edge to access the construction node (after which, you can drag the object back if required – but see below).

Rotation may be limited by the {{w|minimum bounding box}} that is the 'selection box', this is not necessarily the more flush {{w|convex hull}} of the collision-map built into the graphic. Should a corner of the bounding box need to move across the edge of the build-area, it will do nothing more than touch the edge until there is sufficient angle-drag to snap it to the angle from which that corner now comes back away from the edge; or, when it has a long straight edge currently flush with the edge boundary, it may snap to exactly 180°, in rotation, whereupon the opposite long straight edge is flush to the construction area edge. All objects that are drag-moved, similarly, cannot be moved any further than their current bounding box touching the construction-area edging. The bounding box for the rotating wheel is a notable exception to this, being not under any direct angle-control by the player. Instead, it seems to use the bounding inscribed circle that defines the wheel edge iteslf.

Apart from some interactions between the hinged scoops and any element (including other hinged scoops), there is no preventative 'collision detection' between objects during user-placement, which may overlap/cover each other (the most recently spawned item graphically overlays any earlier one). The wheel object will only spin if not constrained by other physical elements (including the spokes of an adjacent wheel, not in counter-rotation) but can still be dragged and placed anywhere within the boundary of the construction area.

The continuous stream(s) of balls respect all ''tangible'' objects, which includes any currently being dragged/rotated, though may prematurely vanish if forced between two items moved to touch/overlap each other. It is possible to to indirectly nudge balls by carefully moving a tangible object's surface into them (or holding them within it, e.g. the "cup"). This may be useful for rescuing temporarily stray balls (before they time-out anyway), unjamming an area with a construction-induced glut ''or'' for testing a ball-path that is not currently being fed 'naturally'. Doing so ''can'' then conceivably fulfil all the exit-gate requirements (temporarily), as it might also transiently spoil some required routing, but the manual intervention will not be possible once a 'machine' has been submit.

===Non-player items===

Ball containers at the bottom of the machine
{|
|[[File:2916_container_red.png|thumb|center|50px]]
|[[File:2916_container_yellow.png|thumb|center|50px]]
|[[File:2916_container_blue.png|thumb|center|50px]]
|[[File:2916_container_green.png|thumb|center|50px]]
|}

Cueball and Megan in the ''USS Buoyancy''
[[File:4d425c.png|thumb|left|150px]]
 

Pit below the ''USS Buoyancy'' (not to scale)
[[File:2916_pit_bottom.png|thumb|left|300px]]
 

=== Color routing ===
The different ball colors have different physical properties. Red balls are more bouncy than other balls, green balls are heavier, and yellow balls are lighter and slightly bouncy. The following values were extracted from the code:
{| class="wikitable sortable"
! Color
! Mass
! Density
! Restitution (bounciness)
! Linear damping (drag)
|-
! data-sort-key="00F" | Blue
| 0.08
| 1
| 0
| 0
|-
! data-sort-key="F00" | Red
| 0.08
| 1
| 0.8
| 0
|-
! data-sort-key="0F0" | Green
| 0.75
| 9.325
| 0
| 0
|-
! data-sort-key="FF0" | Yellow
| 0.024
| 0.3
| 0.6
| 2
|}

For certain combinations of inlet and outlet 'gates', it is necessary to 'cross the streams'. e.g. to direct righthand-entry balls to a lefthand-exit and vice-versa. It is possible to just construct the field to send two (or more!) sets of balls to fly across a common gap, to land on an appropriate reception area that leads to the chosen exit. But, though this is not {{w|Proton pack#Crossing the streams|completely inadvised}}, the timing of the balls cannot be guaranteed to be in sync (or, rather, anti-sync) with each other and collisions ''will'' occur, especially under the variations of delivery that might significantly alter the ballistic path across the gap. Even if the trial machine works, in isolation with a steady stream of all balls entering the field of play, once submitted it will inevitably be fed by a more chaotically-routed preceeding construction.

In order to maintain sufficient correct arrivals at exits, it may be necessary to add a method of filtering the hues.

This could just mean introducing a 'wrong hue trap' beyond any crossing point(s) that send the occasionally wrong ball back to the cross point (or let them time-out in a dead-end, relying upon few enough failures from the rest of the balls, along with all colliding balls that subsequently missed ''any'' chance of reaching an exit). Alternatively, two (or more) feeds of marbles could be fed through a deliberate 'sorter' that does a sufficiently reasonable job of separating the combined sets out towards their intended target-exits.

The various physical qualities of the balls suggest a number of methods for redirecting separate hues to separate onward journeys. This can be done by isolating a hue from every other hue, then passing on (if necessary) to a setup extracting a different one from the remainder, and perhaps also a third time. It may also be possible to merge 'arrangements' of sorting mechanics to efficiently distribute straight into three ''or even four'' onward tracks towards the desired outputs, but that is left as an exercise to the reader.


{| class="wikitable"
! style="background-color:black; color:white" | To separate !! style="background-color:lightblue" | Blue !! style="background-color:lightgreen" | Green !! style="background-color:yellow" | Yellow !! style="background-color:red" | Red
|-
! style="background-color:red" | Red
| *R/B* | '''Use 'bounce''''
The sole difference is how much balls will rebound from objects. Well managed and constrained ricochets should allow a sorting action.
| *R/G* | '''Use mass or 'bounce''''
Green balls cannot be levitated by a vertical fan. An incline across any such fan(s) will levitate only non-Greens. Green, like Blue, rebounds differently to Red. Green balls are also affected by black holes much less than all other balls.
| *R/Y* | ''See Y/B''
| *R/R* style="text-align: center; background-color:black; color:white" | n/a
|-
! style="background-color:yellow" | Yellow
| *Y/B* | '''All methods'''
Yellow, alone, exhibits high drag against any unforced motion. It is also unique in all other ways; e.g. can be levitated highest, against all other hues (though most profoundly against Green).
| *Y/G* | ''See Y/B''
| *Y/Y* style="text-align: center; background-color:black; color:white" | n/a
| *Y/R* style="text-align: center; background-color:gray" | ''See Y/B'' 
|-
! style="background-color:lightgreen" | Green
| *G/B* | '''Use mass'''
Green balls cannot be levitated by a vertical fan. There is also a not so marginal difference in density that might be exploited, such as by using black holes, which only minimally effects Green (perhaps showing an effective difference between mass of attraction and mass of inertia).
| *G/G* style="text-align: center; background-color:black; color:white" | n/a
| *G/Y* style="text-align: center; background-color:gray" | ''See Y/B'' 
| *G/R* style="text-align: center; background-color:gray" | See R/G
|-
! style="background-color:lightblue" | Blue
| *B/B* style="text-align: center; background-color:black; color:white" | n/a
| *B/G* style="text-align: center; background-color:gray" | See G/B
| *B/Y* style="text-align: center; background-color:gray" | See Y/B
| *B/R* style="text-align: center; background-color:gray" | See R/B
|}

Even when not strictly necessary for one's own submission, once submitted into the full playing grid the player's own contribution may find itself working with less 'pure' delivered ball-streams (from an imperfectly separating feed-in contribution). It is possible that this more interactive disruption can make the new setup behave erratically or even entirely incorrectly.

It might be thought good practice (but not ''necessary'') to deliberately combine any or all inputs and do a full job of splitting them again, just in anticipation of possibly having to deal with such cross-contamination and being able to 'clean up' the onward stream(s) for the benefit of others. This would of course be particularly difficult if the isolated building-phase does not provide all four hues to 'test' against, so any speculatively added filtering would have to be added 'blind' (and only on the offchance that any anticipated incorrect balls will actually enter the arena) and without any legitimate exits to which such rejects could be shunted (therefore could accumulate, up until any 'time out' that might apply to any ball once operational as part of the combined grid).

Single-input/single-output designs might not particularly require ''any'' sorting mechanism, in theory, though the unexpected 'contamination' of the system with balls of different masses/etc could perhaps introduce malfunctioning passage from the added chaos it might succumb to.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

:[The placeholder image shows four balls, colored red, green, yellow and blue, bouncing on top of three white blocks. Text in the center: "[visit xkcd.com to view]"]

:[Cueball with lab coat, intro popup]
:Cueball: Balls falling into your cell should be routed to the outputs at a steady rate.

:[Cueball with lab coat, warning popup]
:Cueball: For security reasons, balls that remain in your device for more than 30 seconds will be removed and destroyed.

:[Cueball with lab coat, submit popup]
:Cueball: Congratulations! Your contraption has passed all tests. Press [submit button] to submit it to be added to the machine!

==Trivia==
Once again an April Fool's Day Comic came out late, as Randall did not release this on April 1st, even though April 1st did fall on a Monday, a normal release day. It first came four days later with the Friday release on April 5th. That this is to be considered an April fools' comic, in spite of the later release, was confirmed on the xkcd Facebook page.

*Randall acknowledges the people who helped him create this comic in a [[Header_text#Machine|comic-specific header text]].
**With 11 different involved apart from Randall this is by far the comic with most people involved.
*Some hidden keyboard shortcuts have been found:
** Follow balls: Ctrl + Alt/Option + B (now also accessible by using the button provided)
** Show debug overlay: Ctrl + Shift + Win/Cmd + D
*** This may particularly clash with browser functionality, e.g. Firefox's "New Bookmarks" dialogue which will need closing, though still activating the overlay graphics.
** Delete selected item: Delete (Fn + Delete on Mac)
*When Randall posted a [https://www.facebook.com/TheXKCD/posts/pfbid0Cs97awQZi1ZiaEXouAex9tXrwAS3qJV3RmAiuCq5uvZQwqZVMgDmcqJ7JU9LYodYl link to this comic] on his [https://www.facebook.com/TheXKCD Facebook feed], he directly wrote that it was a late April Fools' Day!
**MACHINE
**Happy Belated April Fool's Day!
**This thus ends any discussion of whether this should be seen as an April Fool's comic or not.
**It just came out 4 days late. This has also happened several times since [[Garden]].
[[File:2916 Machine Facebook April fools' confirmation.png]]

{{comic discussion}}

[[Category:April fools' comics]]
[[Category:Comics with color]]
[[Category:Dynamic comics]]
[[Category:Comics with animation]]
[[Category:Interactive comics]]
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Megan]]
[[Category:Comics featuring Ponytail]]
[[Category:Comics featuring White Hat]]
[[Category:Comics featuring Knit Cap]]
[[Category:Characters with hats]]
[[Category:Squirrels]]
[[Category:Buns]]
[[Category:Cats]]

647: Scary

2024-04-16T00:08:04Z

Blue in real life: and younger than the kid in this comic by the way.....

{{comic
| number = 647
| date = October 9, 2009
| title = Scary
| image = scary.png
| titletext = I'm teaching every 8-year-old relative to say this, and every 14-year-old to do the same thing with Toy Story. Also, Pokemon hit the US over a decade ago and kids born after Aladdin came out will turn 18 next year.
}}

==Explanation==
[[Rob]] is telling his eight-year-old nephew a ghost story, employing such clichéd devices as a flashlight-lit face and stock ghost story endings. The boy is unimpressed, so Rob challenges him to come up with a scarier story. Rob's nephew merely states that he was born after {{w|9/11}}, and yet he is already mentally developed enough to hold a conversation with an adult. This proves effective, as in the final panel Rob assumes the fetal position, gripped by existential dread.

There is no hidden meaning here, but this comic sure is scary for many adults. What's being implied here is that time seems to be moving really quickly and we're getting older faster than we think. Events that seem like they "just happened" have happened long enough ago for a whole other person to come into existence, grow up, and learn to carry on a conversation. Every time we get reminded of this fact, it can be scary, as you then realize that [[1393: Timeghost|you are now closer to your death]]...

9/11 was a terrorist attack in the United States in 2001, on September 11th. Major events such as the assassination of {{w|Assassination of John F. Kennedy|Kennedy}}, the Moon Landing of {{w|Apollo 11}} or 9/11 are easily memorable. It is often said that "everyone remembers where they were when they first heard...". In consequence, these events act as milestones in our memory. They are recalled more vividly, and seem more recent. Today this is maybe also topping the {{w|Attack on Pearl Harbor}} which happened in 1941.

The title text mentions that [[Randall]] is teaching his 8 year old relatives to say the same as in the comic — presumably to the annoyance of his older relatives who will be reminded of the fast passage of time. He does not stop here, but teaches the 14 year old's to say they are born after {{w|Toy Story}} — a major block buster hit from {{w|Pixar}} which came out in 1995. A movie many people will remember fondly and feel just came out the other day... He continues with these scary thoughts by mentioning that {{w|Pokémon}} (1996) came out over a decade ago and that kids born after the big {{w|Disney}} hit movie {{w|Aladdin_(1992_Disney_film)|Aladdin}} from 1992 will turn 18 next year (i.e. in 2010 a year after this comic was published).

[[Randall]] has both before and after this comic tried to [[:Category:Comics_to_make_one_feel_old|make people feel old]] several times.

==Transcript==
:[Rob and his nephew (also drawn like a Cueball, but smaller) are sitting on the ground facing each other. Rob is holding a flash-light up to his face and leans back on the other arm, while crossing his legs. The nephew is sitting forward resting one arm on his lifted knees and leaning back on his other arm.]
:Rob: But they ''never found the ghost's head!''
:Nephew: Lame story, Uncle Rob.
:Rob: And you could do scarier?
:Nephew: Sure.

:[Rob has removed the flash-light from his face and the nephew leans more back and has shifted a leg down so only one knee supports the arm which are now more straight.]
:Rob: Try me.
:Nephew: 9/11 happened before I was born, yet I'm old enough to have this conversation with you.

:[Rob has dropped the flash-light. The nephew has taken the other arm down on the ground. Beat panel.]

:[Rob has curled his legs up to his chin and wrapped his arms around them while the nephew relaxes eve more,]

==Trivia==
*Since 2017-11-05, the time between 9/11 and this comic has been smaller than the time between this comic and the present.
*Since 2019-09-11, some babies born after 9/11 are old enough to vote

{{comic discussion}}

[[Category:Comics featuring Rob]]
[[Category:Comics featuring Cueball]] 
[[Category:Multiple Cueballs]] 
[[Category:Comics to make one feel old]]

647: Scary

2024-04-16T00:05:02Z

Blue in real life: isn't it crazy that i was born after 9/11 but am old enough to vote?

{{comic
| number = 647
| date = October 9, 2009
| title = Scary
| image = scary.png
| titletext = I'm teaching every 8-year-old relative to say this, and every 14-year-old to do the same thing with Toy Story. Also, Pokemon hit the US over a decade ago and kids born after Aladdin came out will turn 18 next year.
}}

==Explanation==
[[Rob]] is telling his eight-year-old nephew a ghost story, employing such clichéd devices as a flashlight-lit face and stock ghost story endings. The boy is unimpressed, so Rob challenges him to come up with a scarier story. Rob's nephew merely states that he was born after {{w|9/11}}, and yet he is already mentally developed enough to hold a conversation with an adult. This proves effective, as in the final panel Rob assumes the fetal position, gripped by existential dread.

No hidden meaning here, but this sure is scary for many adults. What's being implied here is that time seems to be moving really quickly and we're getting older faster than we think. Events that seem like they "just happened" have happened long enough ago for a whole other person to come into existence, grow up, and learn to carry on a conversation. Every time we get reminded of this fact, it can be scary, as you then realize that you are now closer to your death...

9/11 was a terrorist attack in the United States in 2001, on September 11th. Major events such as the assassination of {{w|Assassination of John F. Kennedy|Kennedy}}, the Moon Landing of {{w|Apollo 11}} or 9/11 are easily memorable. For many Americans, 9/11 has acted as an important milestone in their memory, and even those born after the attacks are inundated with their importance and made to feel as if they happened in recent memory.

The title text mentions that [[Randall]] is teaching his 8 year old relatives to say the same as in the comic — presumably to the annoyance of his older relatives who will be reminded of the fast passage of time. He does not stop here, but teaches the 14 year olds to say they are born after {{w|Toy Story}} (a major block buster hit from {{w|Pixar}} which came out in 1995), a movie many people will remember fondly and feel just came out the other day. He continues with these scary thoughts by mentioning that {{w|Pokémon}} (1996) came out over a decade ago and that kids born after the big {{w|Disney}} hit movie {{w|Aladdin_(1992_Disney_film)|Aladdin}} from 1992 will turn 18 next year (i.e. in 2010 a year after this comic was published).

[[Randall]] has both before and after this comic tried to [[:Category:Comics_to_make_one_feel_old|make people feel old]] several times.

==Transcript==
:[Rob and his nephew (also drawn like a Cueball, but smaller) are sitting on the ground facing each other. Rob is holding a flash-light up to his face and leans back on the other arm, while crossing his legs. The nephew is sitting forward resting one arm on his lifted knees and leaning back on his other arm.]
:Rob: But they ''never found the ghost's head!''
:Nephew: Lame story, Uncle Rob.
:Rob: And you could do scarier?
:Nephew: Sure.

:[Rob has removed the flash-light from his face and the nephew leans more back and has shifted a leg down so only one knee supports the arm which are now more straight.]
:Rob: Try me.
:Nephew: 9/11 happened before I was born, yet I'm old enough to have this conversation with you.

:[Rob has dropped the flash-light. The nephew has taken the other arm down on the ground. Beat panel.]

:[Rob has curled his legs up to his chin and wrapped his arms around them while the nephew relaxes even more.]

==Trivia==
*Since 2017-11-05, the time between 9/11 and this comic has been smaller than the time between this comic and the present.
*Since 2019-09-11, some babies born after 9/11 are old enough to vote.
*Since 2022-09-11, babies born after 9/11 are old enough to buy alcohol in the USA

{{comic discussion}}

[[Category:Comics featuring Rob]]
[[Category:Comics featuring Cueball]] 
[[Category:Multiple Cueballs]] 
[[Category:9/11]]
[[Category:Comics to make one feel old]]
[[Category:Kids]]

2918: Tick Marks

2024-04-11T20:04:10Z

Blue in real life:

{{comic
| number = 2918
| date = April 10, 2024
| title = Tick Marks
| image = tick_marks_2x.png
| imagesize = 292x276px
| noexpand = true
| titletext = If you're really savvy, you can hide an entire set of illicit transactions by timing them to draw what looks like a graph inset.
}}

==Explanation==
{{incomplete|Created by a BOT WORKING BEHIND A GRAPH - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

This comic provides the reader with a suggestion on how to "conceal activity" — specifically, in this case, activity happening after what should have been the deadline for completing it — that is going to be graphed over time, by timing bursts of activity with the ticks on the time axis. This is assuming that the scale of the time axis is known, and that the "bottom" of the graph coincides with the line on which the ticks are drawn, rather than the "peak" of the largest tick.

Theoretically, the graphed "activity" would be concealed behind the ticks, meaning anyone reading the graph would perceive activity as having ceased at the deadline, even though it had continued in time-axis-tick-sized bursts afterwards.

The title continues with tips on how to make illicit transactions by integrating them in such a manner that makes them appear to be (or merge into) a graph inset, which would contain relevant information to the graph. For this to work convincingly, it would probably have to be a {{w|scatter plot}} or similar, rather than a {{w|bar chart}} or {{w|line chart}}, upon which carefully crafted datapoints could 'draw' a credible facsimile of [[688: Self-Description|graphical meta-features]]. This reference is timely because the comic came out during tax season, a period when many Americans need to find an explanation for illicit transactions or sources of revenue.

Variations (or possibly inversions) of pretending that actual data is part of the graphical framing device have also been previously seen in the [[1815: Flag|form]] of [[2528: Flag Map Sabotage|flags]].

==Transcript==
:[A graph with two axes is shown. Each axis has tick marks with every fourth mark a bit longer than those in between. The Y-axis is labeled with text rotated 90 degrees clockwise. There is no label on the X-axis. The graph is a jagged curve with three clear peaks; the area beneath the curve is shaded in light gray. After the third and highest peak the curve drops to zero. At the point of decline, a dotted line goes up to a label above the last peak. To the right of this dotted line, the X-axis and the ticks on it are clearly thicker than the axis and the ticks to the left.]
:Y-axis: Activity
:Label: Deadline

:[Caption beneath the panel:]
:If you need to conceal activity, try timing it to hide behind the tick marks on the graph axis.

{{comic discussion}}

[[Category:Line graphs]]

2780: Physical Quantities

2023-05-25T16:19:00Z

Blue in real life:

{{comic
| number = 2780
| date = May 24, 2023
| title = Physical Quantities
| image = physical_quantities_2x.png
| imagesize = 338x183px
| noexpand = true
| titletext = The Hubble length is about 1.9 meters lying down; Edwin Hubble was a tall guy.
}}

==Explanation==
{{incomplete|Created by a TALL SCIENTIST - Do NOT delete this tag too soon.}}

This comic plays on the name of various established physical definitions by simply taking them overly literally. Each one is treated as being a bodily measure of the scientist after which they are named, rather than describing/estimating the objective feature within the scientist's field of study.

;Hubble volume
In cosmology, a {{w|Hubble volume}} (named for the astronomer {{w|Edwin Hubble}}) is a spherical region of the observable universe.
The Hubble volume is approximately equal to 1031 cubic light years (or about 1079 cubic meters).
The value given in the comic is the estimated volume of Edwin Hubble's body.

;Schwarzschild radius
The {{w|Schwarzschild radius}} of a black hole refers to the event horizon: the radius beyond which light cannot escape. Curling up in a ball tends to reduce people's radii, while making them more spherical and easier to measure, so {{w|Karl Schwarzschild}}'s is given as 0.34 m, corresponding to a black hole of about 40 times the mass of Earth.

;Broca's area
{{w|Broca's area}} is part of the brain whose functions are linked to speech. It is not a measurement of area in the sense of length times width. The measurement shown here purports to be the area of {{w|Paul Broca}} (which might refer to the {{w|Body surface area|surface area of his body}}, or the area his body takes up), but it is given in cubic meters (a measure of volume) rather than square meters (a measure of area). (The surface area of an adult human is about two square meters.) This area was recently mentioned in the title text of [[2732: Bursa of Fabricius]].

;Fermi temperature
The concept of Fermi Temperature is {{w|Fermi energy#Related quantities|related to the Fermi Energy}}, a quantum value inherent to very cold substances. The {{w|Human body temperature|temperature of an average human}} is about 37 degrees Celsius, so it makes sense that {{w|Enrico Fermi}}’s temperature was 37 degrees Celsius, when he was alive. Today we can no longer test this, as he died in 1954. {{citation needed}}

;Planck length
{{w|Planck units}} are naturally-derived measurements invented by {{w|Max Planck}}; the Planck length (approximately 1.6×10-35 m) is one of the smallest meaningful distances. However, Randall measures the length of Max Planck, not the units. It is specifically when Planck was lying down (as to not decrease his height from a days exposure to gravity which may shorten a human by a centimeter or so, and also because lying down turns a human’s height into a length).

;Hubble length (title text)
A {{w|Hubble's_law#Hubble_length|Hubble length}} is 14.4 billion light years. This is a joke similar to the above play on the Planck length. The Hubble distance would be the distance between the Earth and the galaxies which are currently receding from us at the speed of light. The joke is that the Hubble length is 14 cm longer than the Planck length because Hubble was a tall man. Another joke by comparing these two are that these two distances are about as far from each other as possible on scales that make sense. The smallest distance to something on the order of the size of the visible universe.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

:[A centered header appears above a list.]
:Reference Physical Quantities
:Hubble volume: 96L
:Schwarzchild radius: 0.34m (curled up)
:Broca's area: 1.7m3
:Fermi temperature: 37°C
:Planck length: 1.76m (lying down)

{{comic discussion}}
[[Category:Comics featuring real people]]
[[Category:Comics with lowercase text]]
[[Category:Astronomy]]
[[Category:Physics]]
[[Category:Biology]]
[[Category:Science]]

2780: Physical Quantities

2023-05-25T03:20:41Z

Blue in real life: /* Explanation */

2746: Launch Window

2023-03-07T12:39:32Z

Blue in real life:

{{comic
| number = 2746
| date = March 6, 2023
| title = Launch Window
| image = launch_window_2x.png
| imagesize = 501x256px
| noexpand = true
| titletext = "Confirmed, we have to scrub." "Ugh, okay. I'll get the bucket and sponge."
}}

==Explanation==
{{incomplete|Created by a WINDEX-SCRUBBED LAUNCH WINDOW - Please change this comment when editing this page. Do NOT delete this tag too soon.}}
A {{w|Launch window}} is a brief period of time in which a spacecraft can be launched from Earth's surface such that the spacecraft can reach its destination with the minimal amount (or an amount lower than a threshhold of acceptance) of energy expenditure.

This comic takes the concept of a "launch window" in a more literal direction, implying that they have an actual physical window that is only open at certain times. One character suggests moving the rocket outside in order to avoid issues that arise from dealing with the window, but gets pushback because moving the rocket outside would cause them to have to deal with more (again, literal) bugs.

The title text is a play on the two meanings of ''scrub'': 1. to rub with a (usually wet) sponge or brush to clean 2. to cancel (here: the launch of the rocket). This continues the comic’s theme of taking aerospace terms literally.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

[First panel: Ponytail and Hairy can be seen sitting behind a console]

Ponytail: The launch window will only be open for another 90 minutes. We may have to scrub.

[Second panel: Slightly zoomed out, left from Ponytail and Hairy, Cueball can be seen behind a console as well]

Cueball: You know, given all our issues with the launch window,

[Third panel: Cueball turns around, facing the others]

Cueball: Have we thought abot moving the rocket outside?

Ponytail: Ugh, no. It's so sunny out.

Hairy: And there are bugs.

{{comic discussion}}
[[Category:Space]]
[[Category: Comics featuring Ponytail]]
[[Category: Comics featuring Cueball]]
[[Category: Comics featuring Hairy]]

2734: Electron Color

2023-02-07T17:55:00Z

Blue in real life: alternate explanation

{{comic
| number = 2734
| date = February 6, 2023
| title = Electron Color
| image = electron_color_2x.png
| imagesize = 568x256px
| noexpand = true
| titletext = There's quark color, but that's not really color--it's just an admission by 20th century physicists that numbers are boring.
}}

==Explanation==
{{incomplete|Created by A SUPER-INTELLIGENT SHADE OF THE COLOUR BLUE - Do NOT delete this tag too soon.}}
In this comic [[Miss Lenhart]] is teaching a school class physics. One of her students ask what the color of electrons is.

This is a relevant question for a kid to ask since on many scientific diagrams of atoms, the subatomic particles have been assigned colors to identify them for the reader. Neutrons are generally red, green, or gray; protons red or green and electrons might be blue or yellow. But there is no general rule so the kid may be confused. Additionally, some scientific diagrams use color coding rather than actually representative colors, and the kid may be wondering what color quarks actually are.

In completely off character style, Miss Lenhart actually gives a correct explanation and states that, unlike the diagrams, which are colored for convenience, the particles are not colored. She even gives the correct explanation for this fact: ''They're too small to interact with visible light, so "color" isn't even defined for them.'' For a more typical Miss Lenhart see for instance [[1519: Venus]].

Of course she then continues by saying that electrons are definitely yellow. If she means they should be yellow on diagrams, because she feels that is to correct way to depict them in drawings of atoms, or if she just teases her young pupils is uncertain. But her off-panel pupils takes her word for it. Presumable the kid who asked question says he knew it, to the fact that electrons are yellow (the first color he mentions in his original question.) He and the other pupils completely ignores what Miss Lenhart just told them. The debate then starts as one pupil claims ''and protons are red?'', and another chimes in, with a ''No, they're gray!'' This only makes sense in a debate of how to draw atoms. Not regarding their actual color, as Miss Lenhart just explained.

The opinions over the colors are probably based on what kind of diagram a persons has initially been exposed, and those 'standard' diagramatic conventions and now forevermore culturally predisposed to different 'correct' interpretations of which hues to use.

Although individual electrons do not have a color, it's possible to produce a solution of [https://chemed.chem.purdue.edu/demos/main_pages/9.4.html 'solvated' electrons], which lend a blue tint to the solvent.

The title text refers to the {{w|color charge}} property of quarks, a property which is part of {{w|quantum chromodynamics}}. As mentioned by [[Randall]], these have nothing to do with color as we know it, but is just a way to represent interactions between quarks in a sufficiently analogous fashion that avoids inventing entirely new words to describe a particular threefold quality of the necessary {{w|color confinement|inter-quark groupings}}. And he jokingly says that the 20th century physicists that came up with the three color system did this as ad admission that numbers are boring. They could just have called the color charge 1 2 and 3.

==Transcript==
:[Miss Lenhart is teaching a class. A boy with spiky hair sits at his desks with his hand raised asking a question. Science Girl sits in front of him looking back at him while leaning an arm on the back of her chair.]
:Miss Lenhart: You have a question?
:Boy: Yeah-What color are electrons and protons? Are they yellow? Red? Blue?

:[Zoom in on Miss Lenhart's head.]
:Miss Lenhart: Subatomic particles don't have a color.
:Miss Lenhart: They're too small to interact with visible light, so "color" isn't even defined for them.

:[Zoom back out but only showing Miss Lenhart. Three pupils reply from off-panel with speech lines coming from starburst at the right edge of the panel.]
:Miss Lenhart: That said, electrons are '''''definitely''''' yellow.
:Off-panel voice 1: I knew it!
:Off-panel voice 2: And protons are red, right?
:Off-panel voice 3: ''What?'' No! They're gray!

{{comic discussion}}

[[Category:Comics featuring Miss Lenhart]]
[[Category:Comics featuring Science Girl]]
[[Category:Kids]] 
[[Category:Physics]]

2724: Washing Machine Settings

2023-01-13T17:57:35Z

Blue in real life: fixed broken link; oops :P

{{comic
| number = 2724
| date = January 13, 2023
| title = Washing Machine Settings
| image = washing_machine_settings_2x.png
| imagesize = 308x524px
| noexpand = true
| titletext = I guess the engineers who built my dishwasher MIGHT have some insight into how to load it, but instead of reading the booklet they gave me, it seems easier to experiment for years and then get in arguments so heated that I get banned from Quora.
}}

==Explanation==
{{incomplete|Created by a WASHING MACHINE MANUAL - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

Cueball starts thinking about what settings to use on his washing machine, and starts planning to look up detailed information on what the settings do and when to use them. However, he doesn't realize that all the information he is looking for can be found by looking at his product manual.

The title text proposes deliberately ignoring the manual for a dishwasher and continuing to use the internet and other people for information on household devices, as with in the comic itself. It references [http://quora.com Quora], a website which allows users to publicly ask questions and answer the questions of others. This website is not typically known for its debates, although the situation in this comic could probably lead to one - when someone who doesn't really understand the subject provides an answer, it could lead to a lengthy and unnecessary argument as multiple parties, at least one of them being incorrect, continue to stand their ground rather than be persuaded. Although Quora moderation is notably inconsistent, being inflammatory (as people tend to be in debates that progress too long) could lead to one's account being reported and banned, like on a typical social network or forum.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

:[Cueball is standing in front of a large combination washing machine/dryer, holding a coat, wondering.]

:Cueball: Okay, do I want "Colors (light)" or "Delicate"? Does delicate mean less agitation? Or a slower spin?

:Cueball: I should google, I bet clothing experts have experimented with various settings/clothing combos.

:Cueball: Ooh, someone should make a tool that indexes people's results by washer model, so you can look up what settings to use for a given...

:[Caption below the panel]:
: Every now and then I forget that product manuals exist and spend a while reinventing them.

{{comic discussion}}

[[Category:Comics featuring Cueball]]

2724: Washing Machine Settings

2023-01-13T17:55:08Z

Blue in real life: title text explanation, plus "combination" "combo" is redundant

{{comic
| number = 2724
| date = January 13, 2023
| title = Washing Machine Settings
| image = washing_machine_settings_2x.png
| imagesize = 308x524px
| noexpand = true
| titletext = I guess the engineers who built my dishwasher MIGHT have some insight into how to load it, but instead of reading the booklet they gave me, it seems easier to experiment for years and then get in arguments so heated that I get banned from Quora.
}}

==Explanation==
{{incomplete|Created by a WASHING MACHINE MANUAL - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

Cueball starts thinking about what settings to use on his washing machine, and starts planning to look up detailed information on what the settings do and when to use them. However, he doesn't realize that all the information he is looking for can be found by looking at his product manual.

The title text proposes deliberately ignoring the manual for a dishwasher and continuing to use the internet and other people for information on household devices, as with in the comic itself. It references [[Quora||http://quora.com]], a website which allows users to publicly ask questions and answer the questions of others. This website is not typically known for its debates, although the situation in this comic could probably lead to one - when someone who doesn't really understand the subject provides an answer, it could lead to a lengthy and unnecessary argument as multiple parties, at least one of them being incorrect, continue to stand their ground rather than be persuaded. Although Quora moderation is notably inconsistent, being inflammatory (as people tend to be in debates that progress too long) could lead to one's account being reported and banned, like on a typical social network or forum.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

:[Cueball is standing in front of a large combination washing machine/dryer, holding a coat, wondering.]

:Cueball: Okay, do I want "Colors (light)" or "Delicate"? Does delicate mean less agitation? Or a slower spin?

:Cueball: I should google, I bet clothing experts have experimented with various settings/clothing combos.

:Cueball: Ooh, someone should make a tool that indexes people's results by washer model, so you can look up what settings to use for a given...

:[Caption below the panel]:
: Every now and then I forget that product manuals exist and spend a while reinventing them.

{{comic discussion}}

[[Category:Comics featuring Cueball]]

2712: Gravity

2022-12-18T04:51:24Z

Blue in real life: down

{{comic
| number = 2712
| date = December 16, 2022
| title = Gravity
| image = gravity_2x.png
| imagesize = 740x700px
| noexpand = true
| titletext = It's a long way down.
}}

*To experience the interactivity, visit the [http://xkcd.com/2712/ original comic].
==Explanation==
{{incomplete|Created by THE UNIVERSE FROM A PIECE OF FAIRY CAKE- Please change this comment when editing this page. Do NOT delete this tag too soon.}}
In this interactive comic, the viewer pilots a small spaceship throughout a vast area in space. The viewer is capable of exploring various bodies and planets within the play area, many containing easter eggs alluding to What If? 2 and previous xkcd comics. The flight mechanics are largely, if not entirely, Newtonian, so the vessel is capable of using the gravity of planets to alter its trajectory or even enter orbit. The spaceship has several indicator circles around it which appear when a gravitational body comes into range, showing the direction towards their center of gravity and the size of the body.

The arrow keys rotate the spaceship and accelerate it forward and backward. On mobile the comic will full screen, pressing either side of the center rotates the spaceship, and pressing in the center accelerates it forward. There is no way to accelerate backward on mobile.

It is fairly easy to fly between planets as long as you pay attention to orbital mechanics don't just floor the accelerator. The background stars show your velocity and orientation relative to the nearest gravity well. If you are having difficulties navigating space, point towards a gravity orb and accelerate for only a few seconds. Wait until the background stars spin wildly, and then reduce your velocity to 0 before gently accelerating towards to object.

There is no "universal" point of view — the bottom of the window, "down", is oriented towards the object exerting the most gravity upon the player. Multiple things found in this comic draw attention to this, such as how on Earth Ponytail says to White Hat, "I checked downforeveryoneorjustme.com and it says just me", and he replies "Yeah, I guess down isn't down for everyone."

Throughout the play area are coins that change the spaceship into different rockets and non-space based vehicles, including humans.

The comic promotes Randall's new book [https://xkcd.com/what-if-2/ What If? 2], which was released in September and is available for purchase. Many of the planets contain references to various What If? articles.

The comic is similar to [[1608: Hoverboard]], which celebrated Thing Explainer instead.

===Celestial Bodies===

The following is an incomplete table of features:

{|class="wikitable sortable"
!
!
!
!
! colspan="4"|References
!
|-
! ID
! Description
! Transcript
! Tiles (X, Y)
! What If
! XKCD
! Movies
! Other
! Explanation
|-
|<code>origin</code>
|'''Starting planet'''
|
|(0, 0)
|
|
|
|
|The starting planet. The player begins on the launch pad in a landed position. Collecting the orbiting cannonball will transform you into a more advanced rocket.
|-
|<code>earth</code>
|'''Earth'''
|
|(27867,-35648)
|
|
|
|
|A planet with among other things; a crane dropping a comet onto a dinosaur, unusually high speed squirrels, Megan inviting Cueball into a pool, a region where the frame rate is intentionally limited, a flagpole, a literal rabbithole referencing the figuratively speaking rabbit hole, someone aiming at a satellite with an arrow, a lake with an eel, the earth-moon firepole, a volcano, two figures being attacked by a third with a sword, two kids playing soccer (Catching the ball will turn the ship into a soccer ball), a farmer on a tractor being stuck in what seems elastic earth, a banana pile, Megan and Cueball digging a hole (in the center of this planet is the "earth's core" referenced below, the Niagara Falls water being redirected into the LHC, Japan(?) leaving earth, a tube to the bottom of the ocean and a reference to everyoneorjustme.com
|-
|
|Earth's core
|
|
|
|
|
|
|[[Cueball]] and [[Megan]] floating in a small space in the center of the planet in inverted rotations.
|-
|<code>europa</code>
|'''Europa'''
|
|(13180, -2540)
|
|
|
|
|Europa, one of Jupiter's many moons (in real life). A broken, icy crust has a single path into its core.
|-
|
|Europa's crust
|"It's so unfair we don't get to compete in EuroVision."
"The region of the solar system where liquid water can exist on the surface is the habitable zone, and the region where it can exist beneath the surface of moons is the Eurozone."

"WHIRRRR"
|
|Y
|
|
|
|Europa's crust, with a single entrance into the core demarcated by an octopus leaving a hole.
Cueball states that Europa is in the Eurozone, a pun on the ''other'' Eurozone, with liquid underneath its surface.

A roomba whirs across the icy crust.

Cueball has a hairdryer and is melting the surface of the crust. A direct reference to [https://what-if.xkcd.com/35/ What If's Hairdryer].
|-
|
|Europa's core
|"We've always used neutrinos for astronomy, but if we place my 'optical telescope' in orbit above the kryosphere, we could potentially observe the universe using electromagnetic waves. Who knows what else there is out there besides stars! There could be other worlds!"
"Hi, I'm Annie. Welcome to the depths of Europa. There's some weird stuff down here."
"We were caught in a powerful November gale on the Great Lakes outside Whitefish Bay. Our ship foundered and sank here." "This is Jupiter's moon Europa." "It was a REALLY powerful gale."
"Does our book club really need this much secrecy?" "That sounds like a question a SPY would ask."
|
|
|
|
|
|A watery ocean with octopi looking out into the great unknown using telescopes. This is a reference to octopus's intelligence here on earth! There's also a secret path leading to a book club, through the wreck of the Edmund Fitzgerald.
|-
|<code>b612</code>
|'''B-612'''
|"Asteroid deflection mission to earth. The package is delivered. Commencing planetary threat neutralization."
|(2610,3700)
|
|Y
|
|
|A reference to [https://xkcd.com/618/ Asteroid]. The little prince is having his asteroid blown up as it was heading towards Earth, apparently.
|-
|<code>dogplanet</code>
|'''Dog park planet'''
|
|(1240, 11230)
|
|
|
|
|A planet with a dog park. Covered in dogs, along with dog walkers and some fences. There's a hole being dug by two dogs and a dog bone empty space in the center.
|-
| <code>goodhart</code>
|'''What If? 2 scenario planet'''
|
|(-13300,-3260)
|
|
|
| Y
| Contains a reference to Kerbal Space Program, whimsically referring to the launchpad as the Vehicle Disassembly Building.

Contains a figure in a cave saying "MMM SPIDERS HOMF NOMF", which may be a reference to the [https://reallyreallyreallytrying.tumblr.com/post/40033025233/average-person-eats-3-spiders-a-year-factoid Spiders Georg] meme.
|-
|<code>sun</code>
|'''The Sun'''
|
|(-14950, 12080)
|
|
|
|
|Difficult to escape from if you hit the core.
|-
|
|Sun's core
|
|
|Y
|
|
|
|Difficult to escape from. Can be escaped by rotating around the sun until an escape-like velocity could be reached.
|-
|<code>soupiter</code>
|'''Soupiter'''
|"I think it's chicken noodle? Hard to tell."
|(-800, -9040)
|Y
|
|
|
|A planet made of soup, with a core. As commented by Cueball, noodle soup. Has several small versions of other planets floating around it.
|-
|<code>nojapan</code>
|'''Earth without Japan'''
|"Something is missing."
|(-7680, -5850)
|Y
|
|
|
|Earth, except it's missing japan.
|-
|<code>japanmoon</code>
|'''Just Japan'''
|
|(-5930, -5800)
|Y
|
|
|
|A moon with water surrounding... just Japan.
|-
|<code>pigeons</code>
|'''A blob labeled "Pigeons"'''
|
|(-9020, -2490)
|Y
|
|
|
|A reference to Chapter 6 of What If? 2, where it would take 1.6 x 10^25 pigeons to lift you and a chair up to the halfway point of Australia's Q1 skyscraper.
|-
|<code>enterprise</code>
|'''Starship Enterprise'''
|
|
|
|
|Y
|
|Star Trek reference: The Enterprise-C, yes 2344,commanded by Captain Garrett's. While defending a Klingon outpost, the weapons discharges resulted in the creation of a temporal rift, through which the badly damaged Enterprise drifted. In the comic, there is a large, invisible gravity distortion near the Enterprise-C
|-
|<code>qwantz</code>
|'''Dinosaur planet'''
|"Welcome... to Jurassic Park."
| (20403,-49559)
|
|
|Y
|
|An homage to [https://www.qwantz.com/ Dinosaur Comics], a webcomic Randall has mentioned several times before. All the dinosaurs on the planet are black-and-white versions of the clip art dinosaurs in that comic. Also references the Jurassic Park movies, with CEO John Hammond welcoming paleontologists Dr. Sattler and Dr. Grant to the planet. The long grass depicted is a plot point in later films.
|-
|
|'''What If? 1 scenario planet'''
|
|
|
|
|
|
|
|-
|<code>roads</code>
|'''Cat blocking traffic flowing through portals'''
|
|
|
|
|
|
|
|-
|<code>outside</code>
|'''Edge of the Universe'''
|
| ( 6081, 26138 )
|
|
|
|
|It looks like a planet labeled "edge of the universe". Outside the universe, so inside the "edge of the universe planet", is another universe, the bubble universe. Hidden entrance is between 10 and 11 'o clock.
|-
|<code>roads</code>
|'''A tree larger than the planet it's growing on'''
|
|
|
|Y
|
|
|May be a reference to [https://www.explainxkcd.com/wiki/index.php/2:_Petit_Trees_(sketch) Petit Trees]. More probably, a reference to ''The Little Prince'', a french children's novel about a traveler from a distant asteroid. In the novel, baobab trees are a serious threat to the Prince's home asteroid, as they are so large that their roots would engulf the asteroid entirely. Randall has alluded to The Little Prince numerous times before, especially in what-if articles.
|-
|<code>outside</code>
|'''Milliways'''
|
| in code: <code>[0,-14500]</code> in game: <code>[0,29000]</code>
|
|
|Y
|Y
|A reference to Milliways, the Restaurant at the End of the Universe from ''The Hitchhiker's Guide to the Galaxy''. On one side of the planet, Ponytail, Cueball, Megan, and other characters gather on the patio of the Milliways restaurant; on the other side, the Sojourner rover examines a rock.
|-
|<code>greatattractor</code>
|'''The Great Attractor'''
|
|
|
|Y
|
|
|Beret Guy stands on the surface of a large ball labeled "The Great Attractor". Gravity is so strong that escaping is impossible.
|-
|<code>present</code>
|'''Present'''
|"I didn't do any of my Christmas shopping yet because I was too busy drawing tiny planets."
"I'm done with my shopping! I got everyone What if? 2"

"...You got me my own book?"

"Yeah! I figured that since you wrote it, it must be right up your alley."

"It does make a good gift, though. You can get it at xkcd.com/whatif2"

"I got you this present!"

"Is it an angry bobcat?"

"It might not be."
|in code: <code>[22820,-18920]</code> in game: <code>[45640,37840]</code>
|
|Y
|
|
|The XKCD cast react to giving each other What if 2? as a present. Gravity at the bottom of the missing quarter of the planet is inescapable. Black Hat gives Cueball a "gift" which he claims "might not be a bobcat", a reference to [[A-Minus-Minus]]
|-
|<code>maw1</code>, <code>maw2</code>, ... <code>maw14</code>
|'''Black hole cluster'''
|
|
|
|
|
|
|A cluster of black holes with extremely high gravitational strength, set to the maximum of 2048. Not particularly easy to land on with multiple conflicting gravitational fields, but once landed on, rather difficult to escape.
|-
|<code>remnant</code>
|'''Remnant'''
|"All right, that's close enough"
"Oh no"

{{w|Walkin' on the Sun|"So don't delay, act now, supplies are running out"}}

"In 5 billion years, the Sun will run out of fuel and suffer gigennial burnout."

"The immense gravity of the sun's remnant means that this is the tallest possible skyscraper."
|(19620, 3800)
|
|
|
|
|A stellar remnant, with high gravity (making it difficult to escape, although it's possible to achieve escape velocity by flying sideways). Has various small landmarks, including a "skyscraper" and suspension bridge. There are bombs being dropped from above the planet, with one that seems to be sledding on the planet.
|-
|<code>steerswoman</code>
|'''Steerswoman Planet'''
|"As a Steerswoman, I have to answer any question anyone asks me, or I'm expelled from the order."
"What's one question that you would be unwilling to answer?"
"Oh no."

"Handle this artifact with great care. It contains a magical wizard's potion which the ancients called 'trinitrotoluene'"
|(-35070,-2500)
|
|
|
|
|A reference to the Steerswoman series of books by Rosemary Kirstein. Includes a number of references to the series, including a group of people observing a small object orbiting the planet.

Trinitrotoluene is better known as {{w|TNT}}, a powerful explosive.
|-
|<code>peeler</code>
|'''Peeler'''
|
|(-9270, 620)
|
|
|
|
|A reference to the question posed by "What If 2: Lose Weight the Slow and Incredibly Difficult Way". A large potato peeler is seen removing the earth's crust.
|}

===Ships===
{|class="wikitable sortable"
|-
! Name
! Description
! Location
! Filename
! Image
|-
|Default
|The starting ship.
|
|ship2
|
|-
| Tintin
|
| On the starting planet; can be obtained by collecting the cannonball in orbit
| ship-tintin
|
|-
| Figure
|Stick figure
|On Goodhart
|ship-figure
|
|-
| Soccer ball
| Soccer ball shaped ship
| On Earth
|ship-soccerball
|
|-
|Alternative Ship
|Slightly thicker version of default ship
|
|ship1
|}

==Data Dump==

extracted from a JSON blob near the bottom of <code>https://xkcd.com/2712/comic.js</code>.
I believe this to be all the data but i'm not sure. this should probably be on a different page but i'll leave that up to the smart people
<pre style="height:10em;overflow-y:scroll;">
{
"items": {
"coin-cannonball": {
"consumable": "yes",
"effect": "transformship|ship-tintin",
"image": "coin",
"loc": [
359,
-815
],
"size": [
40,
40
]
},
"coin-figure": {
"consumable": "yes",
"effect": "transformship|ship-figure",
"image": "figure",
"loc": [
-15050,
-2984
],
"size": [
40,
40
]
},
"coin-regular": {
"consumable": "yes",
"effect": "transformship|ship2",
"image": "regular",
"loc": [
-29976,
-8077
],
"size": [
40,
40
]
},
"coin-soccerball": {
"consumable": "yes",
"effect": "transformship|ship-soccer",
"image": "soccerball",
"loc": [
15293,
11140
],
"size": [
40,
40
]
}
},
"locations": {
"b612": {
"gravity": 60,
"height": 2048,
"loc": [
2610,
3700
],
"radius": 82,
"width": 2048
},
"dogplanet": {
"gravity": 300,
"height": 2048,
"loc": [
1240,
11230
],
"radius": 337,
"width": 2048
},
"earth": {
"gravity": 21000,
"height": 16384,
"loc": [
14360,
14360
],
"radius": 3275,
"width": 16384
},
"enterprise": {
"gravity": 200,
"height": 2048,
"loc": [
1010,
30440
],
"radius": 160,
"width": 2048
},
"europa": {
"gravity": 5000,
"height": 8192,
"loc": [
13180,
-2540
],
"radius": 1625,
"width": 8192
},
"goodhart": {
"gravity": 5000,
"height": 8192,
"loc": [
-13300,
-3260
],
"radius": 1625,
"width": 8192
},
"greatattractor": {
"gravity": 450000,
"height": 4096,
"loc": [
-297000,
-125000
],
"radius": 800,
"width": 4096
},
"japanmoon": {
"gravity": 50,
"height": 2048,
"loc": [
-5930,
-5800
],
"radius": 67,
"width": 2048
},
"maw1": {
"gravity": 2000,
"height": 2048,
"loc": [
-31576,
-9077
],
"radius": 18,
"width": 2048
},
"maw10": {
"gravity": 2000,
"height": 2048,
"loc": [
-29516,
-6321
],
"radius": 15,
"width": 2048
},
"maw11": {
"gravity": 2000,
"height": 2048,
"loc": [
-29381,
-6248
],
"radius": 12,
"width": 2048
},
"maw12": {
"gravity": 2000,
"height": 2048,
"loc": [
-26832,
-5928
],
"radius": 18,
"width": 2048
},
"maw13": {
"gravity": 2000,
"height": 2048,
"loc": [
-31743,
-4724
],
"radius": 18,
"width": 2048
},
"maw14": {
"gravity": 2000,
"height": 2048,
"loc": [
-26071,
-10824
],
"radius": 18,
"width": 2048
},
"maw2": {
"gravity": 2000,
"height": 2048,
"loc": [
-30211,
-8831
],
"radius": 18,
"width": 2048
},
"maw3": {
"gravity": 2000,
"height": 2048,
"loc": [
-27975,
-8266
],
"radius": 18,
"width": 2048
},
"maw4": {
"gravity": 2000,
"height": 2048,
"loc": [
-29546,
-7971
],
"radius": 18,
"width": 2048
},
"maw5": {
"gravity": 2000,
"height": 2048,
"loc": [
-29791,
-7631
],
"radius": 18,
"width": 2048
},
"maw6": {
"gravity": 2000,
"height": 2048,
"loc": [
-29328,
-7575
],
"radius": 18,
"width": 2048
},
"maw7": {
"gravity": 2000,
"height": 2048,
"loc": [
-29700,
-7426
],
"radius": 18,
"width": 2048
},
"maw8": {
"gravity": 2000,
"height": 2048,
"loc": [
-29165,
-7160
],
"radius": 18,
"width": 2048
},
"maw9": {
"gravity": 2000,
"height": 2048,
"loc": [
-30772,
-6910
],
"radius": 18,
"width": 2048
},
"nojapan": {
"gravity": 80,
"height": 2048,
"loc": [
-7680,
-5850
],
"radius": 200,
"width": 2048
},
"origin": {
"gravity": 1500,
"height": 4096,
"loc": [
0,
0
],
"radius": 630,
"width": 4096
},
"outside": {
"gravity": 200,
"height": 16384,
"loc": [
0,
-14500
],
"radius": 125,
"width": 16384
},
"peeler": {
"gravity": 50,
"height": 2048,
"loc": [
-9270,
620
],
"radius": 40,
"width": 2048
},
"pigeons": {
"gravity": 100,
"height": 2048,
"loc": [
-9020,
-2490
],
"radius": 160,
"width": 2048
},
"present": {
"gravity": 300,
"height": 2048,
"loc": [
22820,
-18920
],
"radius": 195,
"width": 2048
},
"qwantz": {
"gravity": 1400,
"height": 4096,
"loc": [
11060,
24870
],
"radius": 850,
"width": 4096
},
"remnant": {
"gravity": 9000,
"height": 4096,
"loc": [
19620,
3800
],
"radius": 537,
"width": 4096
},
"roads": {
"gravity": 40,
"height": 16384,
"loc": [
13240,
-11510
],
"radius": 30,
"width": 16384
},
"soupiter": {
"gravity": 1300,
"height": 4096,
"loc": [
-8000,
-9040
],
"radius": 812,
"width": 4096
},
"steerswoman": {
"gravity": 600,
"height": 4096,
"loc": [
-35070,
-2500
],
"radius": 520,
"width": 4096
},
"sun": {
"gravity": 9000,
"height": 16384,
"loc": [
-14950,
12080
],
"radius": 540,
"width": 16384
}
},
"player": {
"animation": "player.png",
"animcount": 4,
"startloc": [
0,
750
],
"targetheight": 59
},
"tile_height": 1024,
"tile_source": "tile",
"tile_width": 1024
}

</pre>

==Hacks==
'''Modes''' are activated by opening the Javascript Console (F12 [Or Command-Alt-I in most browsers under Mac OS X] to open Developer Tools, then Console tab) and writing corresponding commands. 
'''Click to expand:''' 

<div class="mw-collapsible mw-collapsed leftAlign" style="width:100%">
 
*'''Speedhack:''' <code>ship.engines = "warp"</code> - Speed hacking, sets speed to 1.4x. set to "standard" to reset to normal speed
*'''Teleport to planet:''' <code>[Comic.voyager.pos.x, Comic.voyager.pos.y] = Comic.planetRects.'''''origin'''''.slice(0,2)</code> - teleport near a planet, in this example near earth. You'll still have to fly a bit towards the nearest planet to reach it. Replace '''''origin''''' with the ID of the planet you want to go to, from the table above.
*'''Teleport to coordinate:''' <code>[Comic.voyager.pos.x, Comic.voyager.pos.y] = '''''[0, -2000]'''''</code> - teleport to an exact coordinate. <code>[0, -2000]</code> happens to take you to the starting area.
*'''Chaos Mode:''' <code>ship.engines="infinite improbability drive"</code> - Seems to randomly teleports the ship
*'''Insta Death:''' <code>ship.shields = false</code> - Kill the player if they land on a planet, the code never sets it to false, so it seems to be always true.
*'''No Clip:''' <code>noclip = true</code> - Enables noclip.
*'''Select ship:''' <code>Comic.ship = "ship-tintin"</code> - Select ship (use filename from list of ships)
*'''Autorotate:''' <code>Comic.cameraRotation = false</code> - View does not rotate with ship)
*'''Goggles:''' <code>ze.goggles()</code> - returns a warning: "they do nothing!". This is a reference to Hoverboard, where ''ze.goggles()'' would give you the ability to see false walls. Which itself is most likely a reference to the Simpsons where Radioactive man complains that his safety goggles do nothing against a deluge of acid.
</div>
 

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

Welcome!

To celebrate the world of what if? 2, here is your very own planet to explore!

Give someone the science question-and-answer book what if? 2 for Christmas:
xkcd.com/whatif2

{{comic discussion}}
[[Category:Space]]
[[Category:Book promotion]]
[[Category:Interactive comics]]
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Megan]]
[[Category:Comics featuring Black Hat]]
[[Category:Bobcats]]

2711: Optimal Bowling

2022-12-15T22:38:38Z

Blue in real life: Rearranged order of paragraphs

{{comic
| number = 2711
| date = December 14, 2022
| title = Optimal Bowling
| image = optimal_bowling_2x.png
| imagesize = 306x670px
| noexpand = true
| titletext = If you want to bowl a strike, the optimal place is almost certainly inside a bowling alley, although with a little luck any establishment uphill from one could also work.
}}

==Explanation==
{{incomplete|Created by a SUPERMASSIVE BOWLING BALL - Need a full analysis of each graph (preferably with input from someone who understands bowling). Do NOT delete this tag too soon.}}

This series of line graphs purports to advise players on how to improve their odds of achieving a strike in the sport of {{w|bowling}} – presumably {{w|ten-pin bowling}}, the most popular version of the sport in the United States. As is typical for Randall, however, things start off halfway reasonable and quickly escalate to the absurd. Among the parameters being measured, that being angle, throwing speed, spinning speed, and weight of the ball, the latter three are on {{w|logarithmic scale}}s, making them encompass ranges larger than would be useful for reference by a bowler, up to values that are physically impossible for a human to achieve. {{Citation needed}}

The first line graph indicates that a bowler has the greatest chance of achieving a strike by aiming the ball directly at the pins, with the chance of a strike decreasing rapidly as the ball is aimed to the left or the right. Even a novice bowler already knows to aim the ball at the pins, not elsewhere. While a novice bowler may have difficulty achieving a 0° angle roll, their roll would still not come close to a -90° or 90° angle (due left or due right), much less a -180° or 180° angle (which, in either case, would be the opposite direction from the pins). Unlike with the other graphs, it is physically possible for a bowler to aim the ball at any angle, albeit not permissible under bowling rules; aiming the ball at an angle which deviates significantly from 0° would create a risk of the ball going into one of the other lanes or missing the lanes entirely, which would annoy or anger other bowlers and employees of the bowling alley.

The second graph indicates that a bowler has the greatest chance of achieving a strike by throwing the ball about 10 m/s (22 mph or 36 kph), with the chance of a strike decreasing as the speed is increased or decreased. Most bowlers cannot throw more than 100 m/s (224 mph or 360 kph) {{Citation needed}}. According to the graph, any throw faster than 100 m/s would cause equipment damage/widespread destruction. The graph ends at the speed of light, as it is physically impossible to throw anything faster.

The fourth graph in this comic illustrates a bowler's probability of a strike with a ball whose mass ranges from 100 kg (2.2 pounds) to close to 1010 kg (over 22 billion pounds), and continues by indicating that balls even larger than that would cause "equipment damage" (up to 1020 kg) or the creation of a black hole (starting from around 1025 kg and up). The last entry on the x-axis of this graph is 1040 kg, which is about 5 billion times the mass of the {{w|Sun}}.

By contrast, the United States Bowling Congress requires all bowling balls to weigh no more than 16 pounds (that is, a mass of no more than 7.257 kg), with no minimum weight. Hence, if the x-axis of the graph ran from, say, 0 to 8 kg, the graph might actually impart some useful information.

The title text continues the trend of providing unhelpful information by stating that the optimal place to stand when trying to bowl a strike is inside the bowling alley. It is quite obvious that if one is to attempt to bowl a strike, they should stand near the pins, hence inside a bowling alley. The title text also mentions the possibility of "any establishment uphill from one" working, with a little luck. This suggests the possibility of rolling the bowling ball downhill, into the bowling alley (possibly ''through'' it) and into the pins.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
:[The header is surrounded on either side by small drawings of two bowling pins and a bowling ball.]
:Data for Optimal Bowling

:[Four line graphs are depicted. Each has a numbered one-word general description in a box at the top, an unlabeled y-axis, and a labeled x-axis. The relevant curve and other comments on each graph are in red.]

:1. Aim
:[The graph's x-axis is labeled from -180° to 180°.]
:Release Direction
:[The red curve on the graph is just above the x-axis at all points except for a steep peak around 0°. The red curve is labeled:]
:Relative Probability of Strike

:2. Speed
:[The graph's x-axis is labeled from 10-1 to 108, with the last point on the x-axis labeled "Speed of Light".]
:Ball Speed (m/s)
:[The red curve on the graph starts at the x-axis for 10-1, reaches its peak around 10, then declines and becomes a dashed line ending around three-quarters of the peak around 102. The remainder of the curve is replaced by two labels:]
:Equipment Damage
:Widespread Destruction

:3. Spin
:[The graph's x-axis is labeled from 0 to 1012.]
:Spin (RPMs)
:[The red curve on the graph starts about halfway from its peak for 0, reaches its peak somewhere between 0 and 1,000, then declines and becomes a dashed line around 1,000, soon after which the remainder of the curve is replaced by two labels:]
:Ball Explodes
:Widespread Destruction

:4. Weight
:[The graph's x-axis is labeled from 100 to 1040.]
:Ball Mass (kg)
:[The red curve on the graph starts just above the x-axis for 100, rises steeply and drops steeply ending just above the x-axis, then becoming a dashed line, all before reaching 1010. The remainder of the curve is replaced by two labels:]
:Equipment Damage
:Black Hole Created

{{comic discussion}}

[[Category:Line graphs]]
[[Category:Comics with color]]
[[Category:Sport]]

2711: Optimal Bowling

2022-12-15T18:53:49Z

Blue in real life: Addressed the use of log scales

2702: What If 2 Gift Guide

2022-11-24T12:06:41Z

Blue in real life: added to category

{{comic
| number = 2702
| date = November 23, 2022
| title = What If 2 Gift Guide
| image = what_if_2_gift_guide_2x.png
| imagesize = 500x878px
| noexpand = true
| titletext = BABIES OR LITERATURE BUT NOT BOTH: Baby shoes
}}

==Explanation==
{{incomplete|Created by an OUT-OF-CONTROL HANDHELD NEUTRINO CYLINDER FOR TEENS. Do NOT delete this tag too soon.}}

The comic is a gift guide matching the interest of the receiver with a gift.

{| class="wikitable"
|+
|-
! Interest !! Gift Idea !! Explanation
|-
| Engineering || The platinum cylinder formerly used to identify the kilogram || This is an object of historical relevance of which only six exist, making it a very expensive or illegal gift.
|-
| Biology || The genomes of the scientists who headed the human genome project || The "International Human Genome Sequencing Consortium," as the {{w|Human Genome Project}} team was known, involved scientists from twenty institutions in six countries. In the US, it was initially led by DNA structure co-discoverer {{w|James Watson}} who was succeeded by {{w|Francis Collins}}. In the UK, the project was led by {{w|John Sulston}}. The teams from other countries' institutions were less prominent and performed substantially less work on the initial sequencing. Gene sequence donor identities were protected so neither donors nor scientists could know whose DNA was sequenced. More than 70% of the reference genome produced by the project came from a single anonymous male donor from Buffalo, New York. None of the project scientists contributed to the donor pool; nor have any of them announced that they had their genomes sequenced independently.
|-
| Physics || A beam of neutrinos delivered through the earth by the LHC || [https://en.wikipedia.org/wiki/Neutrino Neutrinos] interact very weakly with other particles, to the point that they almost always pass straight through matter completely unaffected. This means that particle accelerators can send neutrinos to any other point on Earth by aiming the particle beam into the ground, and the neutrinos pass straight through the Earth. This point is referenced in [https://what-if.xkcd.com/73/ What If? 73]. The low interactivity of neutrinos would also mean that the recipient would be unable to perceive their gift, making this a poor present for anyone except the small proportion of physics aficionados who already have a neutrino detector on-hand.
|-
| Animals || Surprise wildlife encounter (gift-wrapped box with a bobcat inside) || This is a reference to [https://www.explainxkcd.com/wiki/index.php/Category:Bobcats xkcd's rich history of mailing boxed bobcats to people]. This gift would place the recipient in a perilous situation, and, although definitely a wildlife encounter, is not a good gift{{Citation needed}}.
|-
| Law || A vacation to that area of Idaho where you can commit crimes with impunity due to a court district boundary error || This refers to the [https://en.wikipedia.org/wiki/Zone_of_Death_(Yellowstone) "Zone of Death"], a 50-square-mile area of Yellowstone National Park that is in the physical boundaries of Idaho, but in the legal jurisdiction of Wyoming. Because a jury in the United States must be composed of residents of the same district ''and'' state in which the crime was committed, but no one lives in this small area of a National Park, anyone who committed a crime here could not possibly receive a trial, and thus could not legally be punished for said crime in any circumstance. This is an interesting legal loophole, but going to this area does not provide any more value than hearing about it, and could scare your law-enthusiast friend.
|-
| Chemistry || A necklace of element samples whose symbols spell out the recipient's name (note: names like "Katherine" and "Brandon" may cause radiation accidents.) || Novelty necklaces are a common and innocuous gift, and using element symbols in place of the same letter is a common gimmick, such as in the title of Breaking Bad. However, making an object out of whatever element sample corresponds to someone's name could have unpredictable results - some elements in their pure form are too brittle or have too low a melting point for such an application, and some are unsafe. "Katherine" would be made from Potassium (highly reactive), Astatine (rare, '''radioactive''' and has a short half-life), Hydrogen (gaseous at room temperature, flammable), Erbium, Iodine (sublimes into a gas at room temperature), and Neon (gaseous at room temperature). "Brandon" would be made from Boron, Radium ('''radioactive'''), Neodymium, Oxygen (gaseous at room temperature), and Nitrogen (gaseous at room temperature). The problems with element samples could be partially alleviated by allowing compounds rather than pure elements, but the radioactivity would still be a problem, and neon does not form compounds and as such is always gaseous.
|-
| Puzzles || Two goats and a new car || This is a reference to the the [https://en.wikipedia.org/wiki/Monty_Hall_problem "Monty Hall problem"], in which a game show contestant can win only one of the three items. (See [[1282: Monty Hall]] for another cartoon inspired by this problem.) This gift places the recipient within a puzzle which is typically discussed hypothetically, rather than happening in real life. Although a new car is a ''great'' gift, goats are only useful to people with specific professions.
The problem that the recipient would have would likely be how to transport the two goats - it'd be difficult to fit both into a compact car at once, but one can't be left behind unattended.
|-
| Technology || Cybiko® wireless handheld computer for teens (2000) || This device was referenced in [https://xkcd.com/2699/ one of last week's comics], so Randall seems to have a temporary fixation on it. While an interesting example of the history of communication technology and coming from a time when experimentation was common and standards were few, it isn't very useful now, because it is no longer supported, has a communication range of 100 meters (sending text messages via radio) and one can only use it to communicate with users of the same device. However, technology enthusiasts could find it interesting as a collectors' item, so by all means it is one of the most plausible gift ideas on this list.
|-
| Space || Webb telescope personal photoshoot || The Webb telescope belongs to NASA, the ESA and the CSA, and is currently very far from Earth. It is designed to capture distant space objects in previously unseen detail. It is not designed to photograph nearby objects of human size, assuming that that is what photoshoot implies. These circumstances make it both an impossible and impractical gift. Furthermore, unless the recipient of the gift is able to travel a long way from Earth, Webb would have to point at the warm Earth and expose its optics to the Sun, permanently crippling the telescope.[https://webb.nasa.gov/content/about/faqs/faqLite.html This is forbidden by NASA.] On the other hand, a gift experience of being allowed to to take your own snapshot of Webb in position, perhaps with a [https://www.dailymail.co.uk/sciencetech/article-10442913/James-Webb-Space-Telescope-seen-Earth-settles-orbit.html robotic telescope], might be an attractive gift to a space enthusiast!
|-
| Literature || Stephen King's writing desk (he's still using it so you'll have to fight him) || {{w|Stephen King}} is an author lucky enough to have legendary status while still alive. The desk of an author that has died would become an object of historic significance and would likely be either kept for exhibition or auctioned by their respective estate, but as Stephen King still writes, his desk, while valuable, cannot be subjected to the same.
|-
| Philosophy || Out-of-control trolley || This is another gift that places the recipient in the situations that they like discussing hypothetically. This refers to the {{w|trolley problem}}, which places stress on the person forced to make the decision, and exists to make them examine their morals. Facing someone with the hypothetical problem is already not a good gift, but forcing them to live through it in real life is a terrible gift. (See [[1455: Trolley Problem]] for another cartoon inspired by this problem.)
|-
| Psychology || A nice gift with a note saying you don't expect anything in return || This is perhaps the most viable option on this list. This gift plays a psychological game on the recipient, reminding them of the nature of favors and bringing giving something into return into the question. This would cause them stress, making it a bad gift, but a psychologist would hopefully understand it to be a joke.
|-
| (Title text) Babies or literature but not both || Baby shoes || This is a reference to the six-word story [https://en.wikipedia.org/wiki/For_sale:_baby_shoes,_never_worn For sale: baby shoes, never worn] which is often attributed to Ernest Hemingway. Someone with babies, such as expecting or new parents would find baby shoes as a valuable gift for their child. Someone interested in literature would see the reference to a famous work. But someone who understands the reference would possibly also be sad if they simultaneously actually enjoyed babies or have children of their own (since the story implies the seller was expecting a baby but there was an accident).
|}

''[https://xkcd.com/what-if-2/ What if? 2]'' is a book by [[Randall Munroe]], author of xkcd.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

What If? 2 Gift Guide

What if? 2 makes a good gift for anyone who's into science, absurd ideas, or just the universe in general. To order, go to xkcd.com/whatif2, or just type "what if 2" into some random box on your device; it will probably work.

Here are some other gift ideas for hard-to-shop-for science enthusiasts:

Interest - Gift Idea

Engineering - The platinum cylinder formerly used to define the kilogram 
Biology - The genomes of the scientists who headed the human genome project 
Physics - A beam of neutrinos delivered through the earth by the LHC 
Animals - Surprise wildlife encounter (gift-wrapped box with a bobcat inside) 
Law - A vacation to that area of Idaho where you can commit crimes with impunity due to a court district boundary error 
Chemistry - A necklace of element samples whose symbols spell out the recipient's name (note: names like "Katherine" and "Brandon" may cause radiation accidents.) 
Puzzles - Two goats and a new car 
Technology - Cybiko® Wireless Handheld Computer for Teens (2000) 
Space - Webb telescope personal photoshoot 
Literature - Stephen King's writing desk (he's still using it so you'll have to fight him) 
Philosophy - Out-of-control trolley 
Psychology - A nice gift with a note saying you don't expect anything in return. 

{{comic discussion}}

[[Category:Book promotion]]
[[Category:Bobcats]]

2702: What If 2 Gift Guide

2022-11-23T21:44:30Z

Blue in real life: accidentally didn't upload the changes i meant to make due to an edit conflict, this is what the previous summary applies to

2702: What If 2 Gift Guide

2022-11-23T21:42:46Z

Blue in real life: Left some blank because I was too lazy to research them but tried to make an explanation for most; did this on my Wikipedia sandbox and then pasted here so it may have formatting mistakes

2638: Extended NFPA Hazard Diamond

2022-06-28T02:34:01Z

Blue in real life: corrected my own epic citation fails

{{comic
| number = 2638
| date = June 27, 2022
| title = Extended NFPA Hazard Diamond
| image = extended_nfpa_hazard_diamond.png
| titletext = With most labs, the hushed horror stories are about something like dimethylmercury or prions, but occasionally you'll get a weird lab where it's about the soda machine or the drop ceiling.
}}

==Explanation==
{{incomplete|Created by a SUBSTANCE WORTH $500 IN STREET VALUE - Please change this comment when editing this page. Do NOT delete this tag too soon.}}
This comic depicts an extension of [https://en.wikipedia.org/wiki/NFPA_704| NFPA 704], bringing it from 2x2 to 3x3 by adding 5 variously useful and humorous squares.

{| class="wikitable"
|+ Squares and explanations
|-
! Square !! Color !! Comic text !! Explanation
|-
| Top || Red || Flammability || Real NFPA 704 square. Denotes flammability.
|-
| Top Left || Blue || Health Hazard || Real NFPA 704 square. Denotes the danger that the substance poses to living beings in ways other than flammability and reactivity.
|-
| Top Right || Yellow || Instability/Reactivity || Real NFPA 704 square. Denotes how easily the substance reacts with other substances.
|-
| Center || White || (Special Hazard) || Real NFPA 704 square. Contains a symbol with additional notes on the substance. After this point, all squares are made up by Randall.
|-
| Center Left || Green || Number of digits in the street value ($/gram) || Describes the order of magnitude of the price of one gram of the substance when sold illegally and informally. Most common illicit drugs would score 2 in this square.
|-
| Center Right || Dark Purple || How much of a hassle it is to dispose of || Describes in a subjective (or maybe objective?) way how difficult the substance is to dispose of. While many things can be thrown in the trash with no additional procedures{{Citation Needed}}, biohazards that may carry diseases are often disposed of in special containers, and nuclear materials are notoriously difficult to safely dispose of. This square would be useful in limited contexts.
|-
| Bottom Left || Lilac || Number of federal agencies who want to know if you have any || In many countries, including Randall's home country, the USA, the government has agencies dedicated to controlling or limiting the use of regulated substances, due to their use as drugs or as chemical weapons. While any given substance would probably be of one agency's interest, something that is both an environmental hazard and a chemical weapon component could interest, for example, both the Chemical Safety Board and the FBI Counterterrorism Division. This could also allude to the CIA's experiments with LSD, which is illegal to possess as a US civilian.
|-
| Bottom Right || Orange || How many times you have to scrub your hands after touching it before they stop smelling weird || While the real NFPA 704 chart describes properties ranging from unsafe to potentially deadly, this square describes a minor but very real inconvenience. Some things are harder to wash off your hands than others, and, given that most people don't often work with dangerous substances {{Citation Needed}}, this would be a more common, but less relevant, concern for many people.
|-
| Bottom || Black || Number of times it's caused one of those terrifying lab accidents that chemists tell scary stories about late at night || The result of this square, although dependent on how much the substance is researched in labs, can show how scared someone should be in handling the substance in question, especially if the number is more than one. Though the description is vague, this number could show how easy it is to cause ''some'' kind of reaction of a terrifying magnitude with this substance.
|}

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
Know your extended NFPA hazard diamond:

Flammability: 0 (top)

Health hazard: 4 (top-left)

Instability/reactivity: 2 (top-right)

Number of digits in the street value ($/gram): 2 (left)

(Special hazard) (center)

How much of a hassle it is to dispose of: 4 (right)

Number of federal agencies who want to know if you have any: 3 (bottom-left)

How many times you have to scrub your hands after touching it before they stop smelling weird: 1 (bottom-right)

Number of times it's caused one of those terrifying lab accidents that chemists tell scary stories about late at night: 2 (bottom)

{{comic discussion}}

2638: Extended NFPA Hazard Diamond

2022-06-28T02:30:47Z

Blue in real life: corrected my own epic table fail

{{comic
| number = 2638
| date = June 27, 2022
| title = Extended NFPA Hazard Diamond
| image = extended_nfpa_hazard_diamond.png
| titletext = With most labs, the hushed horror stories are about something like dimethylmercury or prions, but occasionally you'll get a weird lab where it's about the soda machine or the drop ceiling.
}}

==Explanation==
{{incomplete|Created by a SUBSTANCE WORTH $500 IN STREET VALUE - Please change this comment when editing this page. Do NOT delete this tag too soon.}}
This comic depicts an extension of [https://en.wikipedia.org/wiki/NFPA_704| NFPA 704], bringing it from 2x2 to 3x3 by adding 5 variously useful and humorous squares.

{| class="wikitable"
|+ Squares and explanations
|-
! Square !! Color !! Comic text !! Explanation
|-
| Top || Red || Flammability || Real NFPA 704 square. Denotes flammability.
|-
| Top Left || Blue || Health Hazard || Real NFPA 704 square. Denotes the danger that the substance poses to living beings in ways other than flammability and reactivity.
|-
| Top Right || Yellow || Instability/Reactivity || Real NFPA 704 square. Denotes how easily the substance reacts with other substances.
|-
| Center || White || (Special Hazard) || Real NFPA 704 square. Contains a symbol with additional notes on the substance. After this point, all squares are made up by Randall.
|-
| Center Left || Green || Number of digits in the street value ($/gram) || Describes the order of magnitude of the price of one gram of the substance when sold illegally and informally. Most common illicit drugs would score 2 in this square.
|-
| Center Right || Dark Purple || How much of a hassle it is to dispose of || Describes in a subjective (or maybe objective?) way how difficult the substance is to dispose of. While many things can be thrown in the trash with no additional procedures[[Citation Needed]], biohazards that may carry diseases are often disposed of in special containers, and nuclear materials are notoriously difficult to safely dispose of. This square would be useful in limited contexts.
|-
| Bottom Left || Lilac || Number of federal agencies who want to know if you have any || In many countries, including Randall's home country, the USA, the government has agencies dedicated to controlling or limiting the use of regulated substances, due to their use as drugs or as chemical weapons. While any given substance would probably be of one agency's interest, something that is both an environmental hazard and a chemical weapon component could interest, for example, both the Chemical Safety Board and the FBI Counterterrorism Division. This could also allude to the CIA's experiments with LSD, which is illegal to possess as a US civilian.
|-
| Bottom Right || Orange || How many times you have to scrub your hands after touching it before they stop smelling weird || While the real NFPA 704 chart describes properties ranging from unsafe to potentially deadly, this square describes a minor but very real inconvenience. Some things are harder to wash off your hands than others, and, given that most people don't often work with dangerous substances [[Citation Needed]], this would be a more common, but less relevant, concern for many people.
|-
| Bottom || Black || Number of times it's caused one of those terrifying lab accidents that chemists tell scary stories about late at night || The result of this square, although dependent on how much the substance is researched in labs, can show how scared someone should be in handling the substance in question, especially if the number is more than one. Though the description is vague, this number could show how easy it is to cause ''some'' kind of reaction of a terrifying magnitude with this substance.
|}

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
Know your extended NFPA hazard diamond:

Flammability: 0 (top)

Health hazard: 4 (top-left)

Instability/reactivity: 2 (top-right)

Number of digits in the street value ($/gram): 2 (left)

(Special hazard) (center)

How much of a hassle it is to dispose of: 4 (right)

Number of federal agencies who want to know if you have any: 3 (bottom-left)

How many times you have to scrub your hands after touching it before they stop smelling weird: 1 (bottom-right)

Number of times it's caused one of those terrifying lab accidents that chemists tell scary stories about late at night: 2 (bottom)

{{comic discussion}}

2638: Extended NFPA Hazard Diamond

2022-06-28T02:28:52Z

Blue in real life: /* Explanation */ Added explanation including table

{{comic
| number = 2638
| date = June 27, 2022
| title = Extended NFPA Hazard Diamond
| image = extended_nfpa_hazard_diamond.png
| titletext = With most labs, the hushed horror stories are about something like dimethylmercury or prions, but occasionally you'll get a weird lab where it's about the soda machine or the drop ceiling.
}}

==Explanation==
{{incomplete|Created by a SUBSTANCE WORTH $500 IN STREET VALUE - Please change this comment when editing this page. Do NOT delete this tag too soon.}}
This comic depicts an extension of [https://en.wikipedia.org/wiki/NFPA_704| NFPA 704], bringing it from 2x2 to 3x3 by adding 5 variously useful and humorous squares.

{| class="wikitable"
|+ Squares and explanations
|-
! Square !! Color !! Comic text !! Explanation
|-
| Top || Red || Flammability || Real NFPA 704 square. Denotes flammability.
|-
| Top Left || Blue || Health Hazard || Real NFPA 704 square. Denotes the danger that the substance poses to living beings in ways other than flammability and reactivity.
|-
| Top Right || Yellow || Instability/Reactivity || Real NFPA 704 square. Denotes how easily the substance reacts with other substances.
|-
| Center || White || (Special Hazard) || Real NFPA 704 square. Contains a symbol with additional notes on the substance. After this point, all squares are made up by Randall.
|-
| Center Left || Green || Number of digits in the street value ($/gram) || Describes the order of magnitude of the price of one gram of the substance when sold illegally and informally. Most common illicit drugs would score 2 in this square.
|-
| Center Right || Dark Purple || How much of a hassle it is to dispose of || Describes in a subjective (or maybe objective?) way how difficult the substance is to dispose of. While many things can be thrown in the trash with no additional procedures[[Citation Needed]], biohazards that may carry diseases are often disposed of in special containers, and nuclear materials are notoriously difficult to safely dispose of. This square would be useful in limited contexts.
|-
| Bottom Left || Lilac || Number of federal agencies who want to know if you have any || In many countries, including Randall's home country, the USA, the government has agencies dedicated to controlling or limiting the use of regulated substances, due to their use as drugs or as chemical weapons. While any given substance would probably be of one agency's interest, something that is both an environmental hazard and a chemical weapon component could interest, for example, both the Chemical Safety Board and the FBI Counterterrorism Division. This could also allude to the CIA's experiments with LSD, which is illegal to possess as a US civilian.
|-
| Bottom Right || Orange || How many times you have to scrub your hands after touching it before they stop smelling weird || While the real NFPA 704 chart describes properties ranging from unsafe to potentially deadly, this square describes a minor but very real inconvenience. Some things are harder to wash off your hands than others, and, given that most people don't often work with dangerous substances [[Citation Needed]], this would be a more common, but less relevant, concern for many people.
| Bottom || Black || Number of times it's caused one of those terrifying lab accidents that chemists tell scary stories about late at night || The result of this square, although dependent on how much the substance is researched in labs, can show how scared someone should be in handling the substance in question, especially if the number is more than one. Though the description is vague, this number could show how easy it is to cause ''some'' kind of reaction of a terrifying magnitude with this substance.
|}

Most of the numbers on the real hazard diamond ({{w|NFPA 704}}) represent scales from 0 to 4 and not actual quantities, but humorously Mr. Munroe assigns some of these to actual quantities, such as number of digits in street value and number of federal agencies interested.

Number of digits in the street value is presumably an indicator of how valuable it would be as an illegal drug.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
Know your extended NFPA hazard diamond:

Flammability: 0 (top)

Health hazard: 4 (top-left)

Instability/reactivity: 2 (top-right)

Number of digits in the street value ($/gram): 2 (left)

(Special hazard) (center)

How much of a hassle it is to dispose of: 4 (right)

Number of federal agencies who want to know if you have any: 3 (bottom-left)

How many times you have to scrub your hands after touching it before they stop smelling weird: 1 (bottom-right)

Number of times it's caused one of those terrifying lab accidents that chemists tell scary stories about late at night: 2 (bottom)

{{comic discussion}}

Talk:2606: Weird Unicode Math Symbols

2022-04-14T02:27:04Z

Blue in real life:

Apparently, nobody knows what U+237C ⍼ means (https://ionathan.ch/2022/04/09/angzarr.html)

Can someone add a column where we try to crowdsource a description for the "mathematical use of symbol" ?

I'm curious what those symbols actually mean, and the unicode titles don't give that much information.

I do not doubt that have enough math geeks on here to find the answer to most of then :-D

Thanks!
[[User:Flekkie|Flekkie]] ([[User talk:Flekkie|talk]]) 01:20, 14 April 2022 (UTC)

i agree w Flekkie's comment
[[User:Blue in real life|Blue in real life]] ([[User talk:Blue in real life|talk]]) 02:27, 14 April 2022 (UTC)

2606: Weird Unicode Math Symbols

2022-04-14T02:25:50Z

Blue in real life: added one line summary above table

{{comic
| number = 2606
| date = April 13, 2022
| title = Weird Unicode Math Symbols
| image = weird_unicode_math_symbols.png
| titletext = U+2A0B ⨋ Mathematicians need to calm down
}}

==Explanation==
{{incomplete|Created by SNAKES OVER THERE - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

This comic proposes joke explanations for various unicode symbols with obscure or no known uses.

{| class="wikitable"
|+ Symbols
|-
! Codepoint !! Symbol !! Unicode Name !! Randall's meaning || Explanation
|-
| U+29CD || ⧍ || Triangle with Serifs At Bottom || Shark || May look like a shark fin sticking out of the water.
|-
| U+23E7 || ⏧ || Electrical Intersection || Traffic circle || May look like a {{w|roundabout}}.
|-
| U+2A33 || ⨳ || {{w|Smash product}} || ''Hashtag'' || Looks somewhat like the symbol for {{w|hashtag}} (#) turned by 45 degrees.
|-
| U+2A7C || ⩼ || Greater-Than with Question Mark Above || Confused alligator || One metaphor used when teaching inequality signs in primary school is that the sign looks like an alligator mouth "eating" the larger number.
|-
| U+299E || ⦞ || Angle with S Inside || Snack || May look like a mouth eating an S, where the S symbolizes some snack food.
|-
| U+2A04 || ⨄ || {{w|Arity|N-ary}} Union Operator with Plus || Drink refill || Looks like a cup with a plus to indicate adding drink to the cup.
|-
| U+2B48 || ⭈ || Rightwards Arrow Above Reverse Almost Equal To || Snakes over there || Looks like two squiggles to represent snakes and an arrow indicating the direction where they may be found.
|-
| U+225D || ≝ || Equal To By Definition || Definitely, for sure || "Def" is understood as "definitely"; the equal sign looks like a double underline, indicating heavy emphasis.
|-
| U+237C || ⍼ || Right Angle with Downwards Zigzag Arrow || Larry Potter || Looks like the letter "L" and a lightning bolt. {{w|Harry Potter (character)|Harry Potter}} is known for having a lightning bolt-shaped scar on his forehead.
|-
| U+2A50 || ⩐ || Closed Union with Serifs and Smash Product || Spider caught with a cup and index card || Spiders or other bugs found within someone's house or workspace may be caught with a glass and something flat, often a card or a magazine, to be released outside.
|-
| U+2A69 || ⩩ || Triple Horizontal Bar with Triple Vertical Stroke || ℍ𝕒𝕤𝕙𝕥𝕒𝕘 || Hash symbol with one extra vertical and horizontal line, or perhaps a hash symbol which has been accidentally double-struck or overprinted.
|-
| U+2368 || ⍨ || APL Functional Symbol Tilde Diaeresis || :/ || Looks like a confused or disappointed face. This usage is in fact common among {{w|APL (programming language)|APL}} programmers, as documented [https://aplwiki.com/wiki/APL_Orchard#Emoticons here].
|-
| U+2118 || ℘ || Symbol for {{w|Weierstrass_elliptic_function|Weierstrass p-function}}|| Snake || This symbol coils around like a long snake, with a tapering-off tail on one end and a small "head" on the other.
|-
| U+2AC1 || ⫁ || Subset with Multiplication Sign Below || "User experience", written sideways || Looks like the letters Ux written sideways; Ux is an abbreviation for {{w|user experience}}.
|-
| U+232D || ⌭ || {{w|Cylindricity}} || Rolling dough between your hands to shape it into a ball || Looks like two flat hands (perhaps like stickfigure arms) rolling a ball between them. Rolling dough between one's hands to make it into a ball is an important step in making many kinds of pastry.
|-
| U+2A13 || ⨓ || Line Integration with Semicircular Path Around Pole || Integral that avoids a bee on the whiteboard || Looks like an {{w|integral}} symbol with a bump that goes around a dot, as if a professor was drawing an integral on a whiteboard but did not want to disturb a bee that had landed right in the path of his pen.
|-
| U+2A0B (title text)|| ⨋ || Summation with Integral || Mathematicians need to calm down || This is a combination of two mathematical symbols. The comment given may make fun of mathematicians' tendency to form increasingly complex expressions in their work.
|-
|}

This comic may have been inspired by [https://ionathan.ch/2022/04/09/angzarr.html this blog post], which went viral (in a limited sense) the same day the comic was published.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

[Title:] Weird Unicode math symbols

[Subtitle:] And their meanings

{|
| U+29CD || ⧍ || Shark
|-
| U+23E7 || ⏧ || Traffic circle
|-
| U+2A33 || ⨳ || Hashtag [the text is slanted counterclockwise]
|-
| U+299E || ⦞ || Snack
|-
| U+2A04 || ⨄ || Drink refill
|-
| U+2B48 || ⭈ || Snakes over there
|-
| U+225D || ≝ || Definitely, for sure
|-
| U+237C || ⍼ || Larry Potter
|-
| U+2A50 || ⩐ || Spider caught with a cup and index card
|-
| U+2A69 || ⩩ || [The word "hashtag" but with extra horizontal and vertical lines]
|-
| U+2368 || ⍨ || :/
|-
| U+2118 || ℘ || Snake
|-
| U+2AC1 || ⫁ || [The words "user experience" rotated counterclockwise 90 degrees]
|-
| U+232D || ⌭ || Rolling dough between your hands to shape it into a ball
|-
| U+2A13 || ⨓ || Integral that avoids a bee on the whiteboard
|}

{{comic discussion}}
[[Category:Unicode]]
[[Category:Math]]
[[Category:Harry Potter]]