explain xkcd - User contributions [en]

Talk:2989: Physics Lab Thermostat

2024-09-24T16:16:25Z

172.69.33.62: Chatgpt

Assuming I did the math right (Units proved the units worked out, but I wouldn't otherwise assume that), holding the energy constant at "room temperature with the normal, global Boltzmann constant" this thermostat varies from 13°C (56°F) on the left to 28°C (82°F) on the right. Holding the ''temperature'' constant gives a much harder to interpret range of energies from 4.2 zeptojoules on the left to 4.0 zJ on the right. Turning those back into temperatures with the normal Boltzmann constant gives 29°C (84°F) to 15°C (59°F). Given the reversed scale, I'd assume the former is the intended interpretation, and this thermostat has no effect on local thermal energy, it just adjusts the temperature scale so the number on your (local physical constant variance-compliant) measuring device matches what you asked for. [[Special:Contributions/162.158.62.243|162.158.62.243]] 05:28, 24 September 2024 (UTC) Will

No matter the scale, I'm sure glad that this one doesn't go up to 11. [[User:Zaktduck|Zaktduck]] ([[User talk:Zaktduck|talk]]) 07:56, 24 September 2024 (UTC)

Looking at the page history, I'm wondering if the "edit conflict" didn't kick in for some people. If [https://www.explainxkcd.com/wiki/index.php?title=2989:_Physics_Lab_Thermostat&diff=next&oldid=351061 this edit] was performed over at least half an hour (quite possible), it would seem that useful edits (submitted after the start of that big addition) got wiped out. Seems unlikely that warnings happened but were deliberately over-ridden. I know this can sort of happen very soon after article creation (usually doubling-up 'first' edits), but it should have highlit any inadvertant re-editing of an interim-changed paragraph. I generally thought. [[Special:Contributions/172.70.85.18|172.70.85.18]] 09:39, 24 September 2024 (UTC) ((Ironically, I got hit by an edit-conflict just now, someone having removed linefeeds above where I'm merely appending this!))

I don't understand it the same way as you guys. Through setting the Boltzmann constant to k=1.380649×10−23 Joules per Kelvin, it's actually the Kelvin that the SI is setting. Thus, changing k in an unchanged universe changes the definition of the Kelvin, and (presumably) of Celsius or Fahrenheit too, meaning that the "temperature" reading of the room is changed without any need for heating or aircon, it's just the number which is adjusted to whatever people ask. --[[Special:Contributions/172.71.164.106|172.71.164.106]] 10:25, 24 September 2024 (UTC)
:I like this explanation. We have a thermostat like that where I work. The numbers change, but the actual temperature does not. --[[Special:Contributions/162.158.158.188|162.158.158.188]] 11:27, 24 September 2024 (UTC)
::As I read it, yes it just changes the thing that relates heat to temperature (thus not changing the sum quantity of heat), but I am not convinced that the derivative idea of Temperature doesn't have some latent qualitative effect upon the experience. The additional amount of heat in a cinder might ignite some flammable substance, the same additional heat in a brick would be barely above its normal temperature, for example. Thus conceivably the temperature from the concentrated heat-source has more bearing upon what results than the less dense 'additional heat' with lower temperature that may never invoke the vapour-threshold/flashpoint.
::Without being able to divorce or disassociate the interdependency (together with density/heat-capacith/etc), I can't be sure that such weirdness won't happen, and would not be surprised if things did (e.g. key phase-changes shift around). Like making inertial and gravitational mass independantly evaluated from each kter (if possible) would have certain real-world implications. (As well as hint that there's far more fundamental 'physics' at work than it is assumed that either/both currently are, in either newtonian or einsteinian respects.)
::I think the explanation can cover both "just recorded different" and "changes physics" in a broad scope (which is somewhat hinted at right now). But it might be in the eye of the reader (and editor) how well it does that. [[Special:Contributions/172.70.86.38|172.70.86.38]] 12:26, 24 September 2024 (UTC)

I note that "AIR" is in all caps. Is it supposed to be an Acronym? 12:28, 24 September 2024 (UTC)
:No, that's just for emphasis: it's only the AIR that changes. [[Special:Contributions/172.71.194.171|172.71.194.171]] 12:33, 24 September 2024 (UTC)
::You are both right. AIR means AIR In Room. Caution: This comment contains recursive text: First you curse, then you curse again. [[Special:Contributions/172.71.167.213|172.71.167.213]] 14:07, 24 September 2024 (UTC)

Huh... Everyone's saying "Energy is constant, Temperature number is changing.". But in that case, why would he be worried about it affecting things other than air? What if the Temperature was constant, and the Energy was what was changing? Then the dial would be doing something, and his concern over it affecting solids and liquids would be more warranted. [[Special:Contributions/172.70.178.137|172.70.178.137]] 15:04, 24 September 2024 (UTC)

The current explanation is terrible: (1) It doesn't explain well, spending way too much time on introductory and trivial pedantry than getting to the point of the joke and the concepts necessary to understand it. (2) It's way too long. And (3) the prose is terrible. My high schoolers wouldn't be allowed to use / as a synonym for "or", but that's just the beginning of the poor style, confusing grammar, and the kind of English which screams neurodiversity and home schooling.

There is no doubt in my mind that ChatGPT can do better. [[Special:Contributions/172.69.33.63|172.69.33.63]] 16:14, 24 September 2024 (UTC)

Talk:2971: Celestial Event

2024-08-15T05:14:25Z

172.69.33.62: /* Big Bang theory */ terrible explanation

Unfortunately, this calculation doesn't account for the eventual end of total solar eclipses due to the tidal recession of the moon. [[Special:Contributions/172.69.246.142|172.69.246.142]] 05:31, 13 August 2024 (UTC)

:This is a great comment! Very much like something Randall would have written for title text. [[Special:Contributions/172.71.146.49|172.71.146.49]] 05:58, 13 August 2024 (UTC)
:: Agreed! Also, it seems like the article should have a footnote or separate section going full Randall, "Based only on the data given in this cartoon, what is the possible range of Randall Munroe's home location?" --[[User:AnnapolisKen|AnnapolisKen]] ([[User talk:AnnapolisKen|talk]]) 18:21, 13 August 2024 (UTC)
::: Speculating about people's addresses online is generally frowned upon, in court if nowhere else. [[Special:Contributions/172.68.14.183|172.68.14.183]] 00:50, 14 August 2024 (UTC)

Are all of these events really statistically independent or are e.g. active northern lights and cicada mergence more or less likely to happen at the same time of the year? {{unsigned ip|172.68.194.201|06:15, 13 August 2024}}

: Ooh, great question. It turns out cicadas only emerge in warm weather, particularly in summer, and <s>you can only see the northern lights in winter</s>. That's bad news for us, our superevent might never happen. [[Special:Contributions/172.69.90.3|172.69.90.3]] 01:03, 14 August 2024 (UTC) — edit: oops, I got it wrong. It turns out you can see them all year round. They're actually happening right now in some parts of the US.

This comic was published the same night that saw both the Perseids meteor shower and an unusually strong northern lights. Strangely, the omission of meteor showers in Randall's account of Celestial Events suggests that this is a coincidence. [[User:Mumiemonstret|Mumiemonstret]] ([[User talk:Mumiemonstret|talk]]) 11:43, 13 August 2024 (UTC)

One eclipse every 350 years is not "1/350" - that would imply the eclipse lasted the whole year. The numerator unit should be a minute or so, vastly changing the result. {{unsigned ip|172.70.39.114|13:16, 13 August 2024}}
: Actually, thanks to unit cancelation, Randall's math checks out. I really really feel that it shouldn't, but it does. It's 1/350 years because what you're calculating is "once every X years". It doesn't actually matter how long an eclipse lasts, so long as it's a sufficiently small amount of time so as to be treated as a single point in time. "When that point in time happens, how frequently will those other things be happening?". You can give that answer in days, years, or whatever other unit of time you prefer. Since we're giving it in years, the number we need is "how often (am eclipse occurs) each year" - [[Special:Contributions/172.68.14.185|172.68.14.185]] 23:32, 13 August 2024 (UTC)
:: Yes, I came back to correct myself on this after more reflection. The implied unit is Event and this is the only such non-dimentionless factor. {{unsigned ip|108.162.245.186|23:40, 13 August 2024}}
: Tru dat, as are the comments regarding changes over time in eclipse parameters and the effects of time approximations. However, if we let "4 minutes" be the mean time of totality for an eclipse, and insert that term (for the record, 7.6E-06) for "1" in "1/350", the equation's solution becomes 4E+14, orders of magnitude greater than the age of the universe and, IIRC, well into its projected "heat death". The joke appears to reside in the proximity of Randall's solution to the commonly-accepted age of the Earth, making the solution "just possible". More "accurate" solutions would not be funny, and we would not have seen this comic.[[Special:Contributions/162.158.41.227|162.158.41.227]] 17:11, 13 August 2024 (UTC)
::In the "1/350years", I took it to mean that the unitless "1" represented a day (within which an eclipse occurs, and across this period would also extend the various other conditions). By treating all other unit-laden values as correctly converted to the number in the term of days (and back-converted to the 'more convenient' billions of years for the result), it probably ...not that I did the mathematics to check this... comes out as Randall suggests.
::If, indeed, the length of an (average, as of Earth's current configuration) eclipse, and all other values were understood as proxies for the "number of eclipse-lengths" (except for the uncloudy sky fraction, which is always a unitless half through cancelling out) then you might end up with a result that's different. But the way to check this is to accept the answer (in billions of years) and all the others with time-lengths (respectively) and work out the rough united-length of the "1" by to identify what unit would best fit that. But I leave that to whoever ''really'' wants to dive that deep into it, as the next logical step beyond mere attempted pedantry. [[Special:Contributions/172.68.205.164|172.68.205.164]] 20:22, 13 August 2024 (UTC)
: Every other 2 billion years, on days when it's cloudy or raining, the neighborhood ''doesn't'' get to see the spectacular show. [[Special:Contributions/162.158.154.98|162.158.154.98]] 19:19, 13 August 2024 (UTC)

There are competing factors with regard to the eclipse. Obviously total eclipses don't last for an entire year {{cn}}, but in the distant past when the Moon was significantly closer, they occurred much more frequently than once every 350 years. Far enough back, the moon was significantly larger in the sky and orbited much more rapidly making total solar eclipses a much more common event (even if nobody with eyes was around to see). Using constants for probabilities when things have significant variation is tricky. [[User:Galeindfal|Galeindfal]] ([[User talk:Galeindfal|talk]]) 14:26, 13 August 2024 (UTC)
:I just added (without having seen the above comment) something that deals with that. Actually, that and the way that the 'beat frequency' may ''just'' fail to create an all-effect maximum due to it not being a strictly repeating frequency (if you have an eclipse on one date, with a "1 event in 350 years" calculation for your location/latitude, it doesn't preclude more than one per 350 years or two separated by vastly more than 350 years - though still likely to get "N+1" eclipses over any given 350xN year period for higher Ns).
:If it's a combinatorial experience of fully periodic frquencies (such as with [[1331: Frequency]] then you can be precise over the beat-frequency, but any statistical perturbation can make a 'full hit' into a 'not-fully hit' event quite easily. At its simplest, though the chances of any given day (or useful fraction of a day) of being clear-skied may be 50%, it's not as simple to say "yesterday was cloudy, tomorrow will be clear", or vice-versa. Perhaps slightly more useful to say that than "the year just gone had no clouds, so this year will be full of them" or imagining that every second you could glance up and see "clouds...", "no clouds...", "clouds...", "no clouds...". The meteorological 'calculations' would never be anywhere near as simple as even the (future-trends modified) far-future predictability of the astronomical effects. The biologist might be able to be reasonably sure that the season-locked emergence of a given cicada brood will actually continue to satisfy ''their'' contribution to the calculation for much longer than the weatherman might (though they'd have to admit to the high probability that an ecological upset would flat out end any chances before any of the other forecasts become too hazy to rely upon).
:So the changing of frequencies over the time of the 9calculated) meta-beat's recurrance will make for an compoundedly-chaotic 'actual' meta-beat (assuming it ever completes). This includes the possibility that it actually re-meshes its individual occurances into an actually far more frequent coincidence (two consecutive cicada emergences could end up ''both'' being accompanied by all the other requirements). Depends how much you take at face-value, rather than as a rough and ready 'approximation' for fun-and-non-profit... [[Special:Contributions/172.68.205.164|172.68.205.164]] 20:22, 13 August 2024 (UTC)

The adjustment due to leap years is far dwarfed by the approximate nature of "20 days" and "2 months" in some of the events. [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 15:06, 13 August 2024 (UTC)

Don't know how it could be calculated in, but there's a fundamental conflict between the solar eclipse and aurora borealis. Solar eclipses are only visible during the day {{cn}}, but the aurorae aren't symmetrical around the poles and drag further equator-ward on the night side of the planet. So the occurrences of Northern lights that would reach to Boston latitudes on the *day side* of the planet so as to be visible during a solar eclipse would be much, much rarer (closer to Carrington-event rarity, currently pitched at once every 100 to 1000 years instead of the 11 Randall used, but even then it'd have to be a particularly strong event). [[Special:Contributions/172.70.230.142|172.70.230.142]] 13:34, 14 August 2024 (UTC)

;Big Bang theory
If he had included all these events happening on a Tuesday or a Thursday then we're getting close to 1 every 14 billion years. A time which everyone's neighbourhoods had a really big show. [[User:Kev|Kev]] ([[User talk:Kev|talk]]) 02:36, 15 August 2024 (UTC)

;Terrible explanation
Someone has to say it. The explanation is so long and convoluted that it serves substantially more to confuse than to explain. Someone please edit it mercilessly. [[Special:Contributions/172.69.33.62|172.69.33.62]] 05:14, 15 August 2024 (UTC)

2957: A Crossword Puzzle

2024-07-10T21:16:59Z

172.69.33.62: /* 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.}}

* 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.
* 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".
* 19 across. The international standard for {{w|paper size}} is A4, here written as AAAA.
* 21 across. {{w|A4 paper}} 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).
* 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."])
* 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.
* 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"
* 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 Vigenere 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)
:32. 2018 Kiefer song
:35. Top Minor League tier
:35. 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}}

2941: Cell Organelles

2024-06-03T20:38:20Z

172.69.33.62: /* Explanation */ eliminate redirect

{{comic
| number = 2941
| date = June 3, 2024
| title = Cell Organelles
| image = cell_organelles_2x.png
| imagesize = 563x451px
| noexpand = true
| titletext = It's believed that Golgi was originally an independent organism who was eventually absorbed into our cells, where he began work on his Apparatus.
}}

==Explanation==
{{incomplete|Created by a GOLGI ENDOPLASMIC RETICULUM. Do NOT delete this tag too soon.}}

The comic depicts a cell diagram with a mix of real and fictional organelles, blending accurate biological terms with misplaced or absurd labels. While it includes actual cell components like the nucleus, mitochondria, and Golgi apparatus, it also inserts unrelated concepts from various fields such as geology, engineering, software, and pop culture. Terms like "evil endoplasmic reticulum" and "sticky endoplasmic reticulum" add a whimsical twist to familiar scientific terms. The comic plays on the complexity and diversity of cell structures by mixing in unrelated and humorous terms, highlighting the often confusing and intricate nature of scientific diagrams with clever wordplay and cross-disciplinary jokes.

The title text adds a humorous and fictional backstory to the Golgi apparatus, an essential cell organelle involved in processing and packaging proteins. It playfully suggests that Camillo Golgi, the scientist who discovered the Golgi apparatus, was originally an independent organism. This organism was supposedly absorbed into our cells, where it then started working on what is now known as the Golgi apparatus. The joke is a satirical take on the endosymbiotic theory, which posits that certain organelles within eukaryotic cells, like mitochondria and chloroplasts, originated from independent symbiotic prokaryotic organisms that were absorbed by a host cell. Golgi appears to be depicted in the comic as a tiny alien being.

{| class="wikitable"
|-
! Label
! Meaning
! Real?
! Cell organelle?
! Joke explanation
|-
| {{w|Carbonation}}
| Carbon dioxide dissolved in a liquid.
| Yes
| No
| Misplaced chemistry term.
|-
| {{w|Cellophane}}
| A thin, transparent sheet made of regenerated cellulose.
| Yes
| No
| Misplaced packaging material term.
|-
| {{w|Chloroplasts}} if you're lucky
| Organelles in plant cells responsible for photosynthesis.
| Yes
| Yes
| Actual cell organelles, only found in plant cells.
|-
| Drain plug
| A stopper for a drain.
| Yes
| Misnomer
| Misplaced plumbing term. Might be referring to pores.
|-
| Evil endoplasmic reticulum
| Not a real term.
| No
| No
| A humorous twist on the actual {{w|endoplasmic reticulum}}, implying a malevolent version.
|-
| Golgi
| {{w|Camillo Golgi}} (1843–1926) was an Italian biologist and pathologist known for his works on the central nervous system, for whom the Golgi apparatus is named.
| Yes
| No
| Not a tiny alien being who merged with our cells as the depiction and title text implies.
|-
| {{w|Golgi apparatus}}
| A complex of vesicles and folded membranes involved in secretion and intracellular transport.
| Yes
| Yes
| Actual cell organelle.
|-
| Human skin
| The outer covering of the human body.
| Yes
| No
| Misplaced anatomical term.
|-
| {{w|Hypoallergenic}} filling
| Materials that do not cause allergic reactions.
| Yes
| No
| Misplaced consumer product term.
|-
| {{w|Lithosphere}}
| The rigid outer part of the earth, consisting of the crust and upper mantle.
| Yes
| No
| Misplaced geological term.
|-
| {{w|Mantle}} 
| The layer of the earth between the crust and the core.
| Yes
| No
| Misplaced geological term. Many other meanings.
|-
| {{w|Midichlorians}}
| Fictional microorganisms in the {{w|Star Wars}} universe, which confer Force sensitivity.
| Yes
| Fictional
| Misplaced fictional term.
|-
| {{w|Mitochondria}}
| Organelles that generate energy for the cell.
| Yes
| Yes
| Actual cell organelles, known as the "powerhouse of the cell."
|-
| Natural flavor
| Flavoring derived from natural sources.
| Yes
| Conceivably
| Misplaced food industry term.
|-
| {{w|Norton AntiVirus}}
| A software product designed to protect computers from malware.
| Yes
| No
| Misplaced software term.
|-
| {{w|Nucleolus}}
| A small dense spherical structure in the nucleus of a cell during interphase.
| Yes
| Yes
| Actual cell organelle, involved in ribosome production.
|-
| Nucleoloulous
| Not a real term.
| No
| No
| A humorous exaggeration of "nucleolus."
|-
| {{w|Nucleus}}
| The central and most important part of an object, forming the basis for its activity and growth.
| Yes
| Yes
| Actual cell organelle which houses genetic material.
|-
| {{w|Nucleons}}
| Protons and neutrons in the nucleus of an atom.
| Yes
| No
| Misplaced physics term.
|-
| {{w|O-ring}}
| A mechanical gasket in the shape of a torus; used to seal connections.
| Yes
| No
| Misplaced engineering term.
|-
| {{w|Pith}}
| The central tissue in plants, used for nutrient transport.
| Yes
| No
| Misplaced botanical term.
|-
| {{w|Pleiades}}
| A cluster of stars in the constellation Taurus.
| Yes
| No
| Misplaced astronomical term.
|-
| {{w|Rough endoplasmic reticulum}}
| Endoplasmic reticulum with ribosomes attached, involved in protein synthesis.
| Yes
| Yes
| Actual cell organelle.
|-
| {{w|Seeds}}
| Plant embryos used for reproduction.
| Yes
| No
| Misplaced botanical term.
|-
| {{w|Slime}}
| A moist, soft, and slippery substance.
| Yes
| Conceivably
| Misplaced term; could refer to a general texture or appearance, not specific to cells.
|-
| {{w|Smooth endoplasmic reticulum}}
| A network of tubular membranes within the cytoplasm of the cell, involved in the transport of materials.
| Yes
| Yes
| Just a standard term for the smooth variant of endoplasmic reticulum.
|-
| Sticky endoplasmic reticulum
| Not a real term.
| No
| No
| A humorous twist on the actual endoplasmic reticulum.
|-
| {{w|Ventricle}}
| A chamber of the heart that pumps blood out.
| Yes
| No
| Misplaced anatomical term.
|-
| {{w|Vitreous humour}}
| The clear gel that fills the space between the lens and the retina in the eyeball.
| Yes
| No
| Misplaced anatomical term.
|-
| Weak spot
| A vulnerable point.
| Yes
| Conceivably
| Cell membrane surfaces do indeed vary in strength, often due to the presence of organelles such as {{w|ion channel pore}}s or similar ducts.
|}

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

{{comic discussion}}

2600: Rejected Question Categories

2023-11-05T04:58:49Z

172.69.33.62: Added explanation about Spaceships and Soup line.

{{comic
| number = 2600
| date = March 30, 2022
| title = Rejected Question Categories
| image = rejected_question_categories.png
| titletext = You can click to preorder to get a copy of What If? 2 when it comes out 9/13, assuming we all make it past the spider situation(?) on Tuesday(?).
}}

==Explanation==
[[Randall]] recently announced, in [[2575: What If? 2]], that he is publishing a new ''[[What If? (book)|What If?]]'' book based on reader-submitted questions. This comic is another [[:Category:Book promotion|promotion]] of the book, and the entire comic is a link to his [https://xkcd.com/what-if-2/ what if? 2] page on xkcd.

This comic shows the [[#Question categories|categories of questions]] he claims to have received, but rejected to use in his book, giving an example question for each category. In typical xkcd fashion, these begin out by being plausible, although often unlikely to have been submitted as a ''what if?'' question, moving in to more and more absurd types of questions, especially with the last question, that appears to be a combination of all previous categories and is therefore marked "?????"

The title text refers to the launch date of the book September 13, rendered in the American style 9/13. This format can be confusing to non-Americans, although usually not when the date is larger than 12, since it would then appear to reference the 9th day of the 13th month. This "13th month" was, however, referenced in the first comic about the book: [[2575: What If? 2]]. See also Randall's take on the date format, {{w|ISO 8601}}, in [[1179: ISO 8601]].

Randall then continues the title text by referencing the second to last category with vague ominous questions. The example question here asks if there is need to worry about spiders after Tuesday. So Randall notes that the release date, 5.5 months after the release of this comic, is of course assuming anyone will survive past next Tuesday (2022-04-05).

Tuesday has been notably referenced in [[277: Long Light]], [[564: Crossbows]], [[1099: Tuesdays]] and most notably in [[1245: 10-Day Forecast]], where it seems that the last day ever will be a Tuesday. Tuesday is the second day of the week, and notably, the Tuesday of the week following the publication of this cartoon (April 5th, 2022) was the Day of the Spiders.

"Spaceships and Soup" is a reference to the first chapter of What If? 2, where Randall looks into filling the Solar System with soup.

==Question categories==
{| class="wikitable"
|'''Category'''
|'''Question'''
|'''Explanation'''
|-
| People cheating on homework
| What if I made a pendulum by hanging a rock on a 2.75 meter string? What would its period be in seconds? (Show your work!)
| This appears to be a physics student trying to get out of doing their work by presenting the question for Randall to answer in ''What If'' (which is a common occurrence on question-and-answer sites such as Stack Overflow). Most school homework requires the student to "show their work", i.e. write out their process of solving the question. Making students show their work serves two purposes: it allows students to score partial credit on an incorrect answer if they show the right methodology and basic understanding even if they make a wrong turn along the way; it also prevents students from simply cheating by looking up the right answer without showing how they got that answer — the student including this caveat in their email is a giveaway as to their tactic (along with the boring nature of their inquiry).
|-
| Medical advice
| What if you got a scratch and the next day your hand looked like this [''📎 attachment'']? Should you see a doctor or what?
| Randall is not a physician, is not qualified to give medical advice, and will not answer medical questions. This was a problem on early Wikipedia which, for a time, required all articles covering medical topics to point to a {{w|WP:MEDICAL|Medical Disclaimer}}. This was also an issue covered in the 1st ''what if?'' book, under Weird and Worrying Questions from the Inbox, where a reader asks about the effects of a toxin on the excretory system. If your body is not behaving in the way you expect, consulting with a medical professional is, in general, a good idea.
|-
| Personal
| Why don't the squirrels in my yard like me???
| Randall has no way of knowing why the wildlife in a given area dislike a specific person, especially if this hints at a specific animosity/belligerence and not just general avoidance of humans as a perceived threat. These kind of questions are common on sites like reddit, and are usually covered by general explanation of animal behaviors unless the asker supplies more information in the comments. However, the choice of squirrels are likely not random since [[:Category:Squirrels|Squirrels]] are a recurring theme on xkcd and has often been [https://www.explainxkcd.com/wiki/index.php/Category:Squirrels#Uses_in_other_xkcd_media: used in what if?] (sometimes as {{what if|105|placeholder}} for a potentially horrible image).
|-
| Spam
| Do you want to meet lonely singles in your area tonight?
| This is a common online popup advertisement and is generally considered undesirable. An unavoidable side effect of Randall having an email address published where the public can find it is that spammers have just as much access to it. Most people do not respond to spam emails, and Randall is no exception.
|-
| Phishing
| Have you recently been the victim of phishing? To check, log in to your account by clicking <u>here</u>.
| Again, because Randall's What-If email is publicly available, phishers have access to it and can probe the recipient for information. Randall is experienced enough to recognize a phishing attempt and ignore it. This type of phishing scam, in which the scammer requests your personal data for the purported purpose of checking if it has been "stolen" thereby "stealing" it himself, has become more common as people have become aware of phishing, and phishers have thus embraced the possibility of exploiting a new niche in the layers of naivete.
|-
| Requests for help with a crime
| Using modern science, what would be the fastest way to get through this bank vault door? [''📎'' blueprints]
| No, Randall is ''not'' going to help a criminal commit breaking and entering or robbery, thank you very much. A common problem{{Citation needed}} with heist movies is that they show a believable{{Citation needed}} method for breaking in to a vault which people then try to replicate in real life. Such movies often portray an expert in some other field being "smart enough" to craft the plan, sometimes unwittingly.
|-
| Unanswerable
| Why am I me and not someone else
| There is a lot in this question that could be unpacked, and Randall doesn't want to touch on any of it.

At face value the question is asking about {{w|Philosophy of mind}}, a branch of philosophy with many questions that are unanswerable due to our own imperfect understanding of mind. The asker is inquiring as to what process is responsible for designating that their consciousness be tied to the body in which they currently reside, as opposed to another body presumed to have consciousness; furthermore, they likely wish to know the mechanics behind how this process works. There is as yet insufficient data for a meaningful answer.

It's also quite possible the asker is feeling melancholic and unsatisfied with their life. Randall doesn't feel qualified to try diagnosing or treating someone's existential depression.
|-
| Vague
| What is going to happen? (Be specific)
| Some humor is derived from the request for specificity in the question, which completely lacks any sort of specificity of its own.
|-
| Vague and ominous
| Will I have to start worrying about spiders after Tuesday?
| This implies some event that occurs on a (possibly next?) Tuesday. This event may relate to spiders in some way, and cause those who do not currently worry about spiders to do so. If you do not currently worry about spiders, this question does not give enough specifics for Randall to intelligently answer whether or not you should start.
Possibly a [[:Category:Red Spiders|red spiders]] reference. Could also be a reference to [[1688: Map Age Guide]] where some dangerous event involving spiders was apparently set to happen in 2022.
|-
| ?????
| Hi, we're lonely singles in your area, and we're wondering what would happen if we shot a nuclear bomb into a volcano! Click here to log in and tell us ...
| If nothing else, this entry is clearly made up by Randall, as it appears to be a combination of as many prior categories as he has room for, specifically Spam, Phishing, and an already-answered question, before getting cut off by the bottom of the panel.

"Would it be possible to stop a volcano eruption by placing a bomb (thermobaric or nuclear) underneath the surface?" was a question featured in the first ''what if'' book. Randall answered with an emphatic "No!"
|}

==Transcript==
In ''What If? 2'' (xkcd.com/whatif2), I answer ridiculous questions sent in by readers about everything from volcanoes to spaceships to soup.

Here are a few of the common types of question that I did ''not'' answer:

[In separate boxes for each category]

[In row 1:]

People cheating on homework: What if I made a pendulum by hanging a rock on a 2.75 meter string? What would its period be in seconds? (Show your work!)

Medical advice: What if you got a scratch and the next day your hand looks like this [''📎 attachment'']? Should you see a doctor or what?

Personal: Why don't the squirrels in my yard like me???

[In row 2:]

Spam: Do you want to meet lonely singles in your area tonight?

Phishing: Have you recently been the victim of phishing? To check, log in to your account by clicking <u>here</u>.

Requests for help with a crime: Using modern science, what would be the fastest way to get through this bank vault door? [''📎'' blueprints]

[In row 3:]

Unanswerable: Why am I me and not someone else

Vague: What is going to happen? (Be specific)

Vague+Ominous: Will I have to start worrying about spiders after Tuesday?

?????: Hi, we're lonely singles in your area, and we're wondering what would happen if we shot a nuclear bomb into a volcano! [partially cut off horizontally:] Click here to log in and tell us

{{comic discussion}}

[[Category:Book promotion]]
[[Category:Physics]]
[[Category:Squirrels]]
[[Category:Spiders]]
[[Category:Nuclear weapons]]
[[Category:Comics with lowercase text]]
[[Category:What If?]]