explain xkcd - User contributions [en]

Talk:3090: Sail Physics

2025-05-17T15:44:50Z

162.158.162.103: annoyed by AI slop

After the last step, the sailors would then need to ground the boat to avoid being pushed in a circle, wouldn't they? [[User:Sophon|Sophon]] ([[User talk:Sophon|talk]]) 20:47, 16 May 2025 (UTC)

Note that for eastward wind, the boat will be propelled upwards, while the opposite is true for westward winds. This provides a basis for the functioning of airships and planes (Helicopters are more complicated, and additionally rely on their own magnetic fields) [[Special:Contributions/162.158.217.45|162.158.217.45]] 21:21, 16 May 2025 (UTC)
: Hence why you should always touch an earthing rod before approaching a helicopter, to avoid the magnetism pulling you into their rotors. [[User:Kev|Kev]] ([[User talk:Kev|talk]]) 03:11, 17 May 2025 (UTC)

Is this actually wrong? Wouldn't it still be ''a'' force on a sailboat, even if it's not the strongest? [[User:Smurfton|Smurfton]] ([[User talk:Smurfton|talk]]) 22:20, 16 May 2025 (UTC)

: I added some explaination on direction and magnitude of the lorentz force, maybe that will help - sga {{unsigned ip|172.68.234.227|22:33, 16 May 2025 (UTC)}}

The explanation states that of the four forces, only the electromagnetic force operates at the macro level. This is incorrect, as gravity is also directly observable by humans. There should also probably be a link to https://en.wikipedia.org/wiki/Airfoil to provide an explanation for how sails actually allow a boat to sail upwind. I recommend removing the remark about the poles potentially flipping in the future, as this is irrelevant. [[Special:Contributions/172.68.55.124|172.68.55.124]] 23:52, 16 May 2025 (UTC)

: What i meant was, for 2 objects at scales of humans =, maybe did not prase it well. In this case, it is the wind and the sail. Wind does not have a "mass" (the atoms most certainly do, but) we essentially have a pressure force, or momentum of wind, where instead of using the energy of atoms (and hence the mass) as given by kinetic theory is not used (that is random (as given by boltzman maxwell statistics)) and uniform (in the sense that for any direction, number of particles going against and towards is equal) and what we have is just pressure applied by a effective "group velocity" of the wind atoms. The gravity interaction between wind and boat, or the local waves and boat is negligible, and planetary gravity is not considered because that is not relavant for in plane motion. the pole fillping was added just for future proofing the article. I am sorry for the puns. I have rewwritten some parts, and reduced the part about pole flipping, and also added the average case scenario for the force, hope it is better now. - sga {{unsigned ip|172.70.143.75|02:37+, 17 May 2025}}
::That is one huge rambling paragraph, if it's (mostly) yours. I'm no stranger to ''writing'' huge rambling paragraphs, myself, but I gave up only a little way in on trying to make it read better. Grammatically, prosaically and with relevence.
::May I suggest that each 'frame' is treated to its own (shorter) paragraph, explaining what effect it tries to convey, what logic it individually tries to follow, but where it fails and what actual forces dominate a true example. (e.g. the hull-shape, including keel, helping convert roughly lateral sideways forces into forward ones against the water; those lateral ones having already been a conversion of largely head-on winds in the first place, thus two "almost up to 90 degree" redirections of force allow ''very nearly'' a 180-degree reversal of wind-blown movement. Feel free to discuss the comparisons and differences between 'flappy sail', though blown taught by the air, and an 'upright aircraft wing' solid design. ...See, told you I could ramble, but someone can surely do better at segmenting and summarising the basics of this.) [[Special:Contributions/172.71.178.32|172.71.178.32]] 08:32, 17 May 2025 (UTC)

This is super embarrassing to admit, but I came here to verify whether this was a serious thing or not. I had no idea how a sailboat sails against the wind. [[User:Catgofire|Catgofire]] ([[User talk:Catgofire|talk]]) 23:58, 16 May 2025 (UTC)
:You aren't alone - I think I was an adult before I understood tacking in the sailboat sense of the word. [[Special:Contributions/162.158.174.127|162.158.174.127]] 02:45, 17 May 2025 (UTC)
: I'm wanting to add in some wisdom about "science-y" explanations that appear to be sensible but are completely wrong, segueing into how generative language models appear to be far more reliable than they are. However this margin is too narrow [[User:Kev|Kev]] ([[User talk:Kev|talk]]) 03:09, 17 May 2025 (UTC)

I've been really annoyed with ExplainXKCD in the last few months ever since the initial posting has always been LLM generated. It requires more brain power to make sense of AI slop and edit it, than to contribute to a blank page. [[Special:Contributions/162.158.162.103|162.158.162.103]]

Any chance we can add an explanation of how it *actually* works? [[Special:Contributions/162.158.216.174|162.158.216.174]] 10:03, 17 May 2025 (UTC)
:Through judicious angling of sail, wind (from any direction other than fully head-on) is deflected(/uses 'wing-effect') to create a force, trying to push the boat, that might be mostly sideways but also a bit forward. Because of the shape of the hull, any sideways force is resisted by the water, reinforcing the remaining forward component which the hull is far more ready to take advantage of. Enough sail (and enough stability to resist rolling) gives a large amount of movement towards, but not ''exactly'' towards, the wind. [[Special:Contributions/172.69.224.72|172.69.224.72]] 10:41, 17 May 2025 (UTC)

The joke is that the most commonly used explanation for why flow over a foil generates lift - particles going one way have a longer way to travel than the other, which generates a difference in speed and therefore a pressure differential - is wrong. {{unsigned ip|172.69.109.91|10:36, 17 May 2025}}

Talk:1323: Protocol

2025-05-08T06:37:07Z

162.158.162.103:

This is funny. I was really drawn into the conversation due to the names. [[Special:Contributions/108.162.246.117|108.162.246.117]] 07:05, 29 January 2014 (UTC)
:Me too! And I'm even more drawn to the meta-conversation!! :) [[User:Nealmcb|Nealmcb]] ([[User talk:Nealmcb|talk]]) 13:30, 29 January 2014 (UTC)
::But what about me? Alice and Bob get way too much time already.... [https://en.wikipedia.org/wiki/Alice_and_Bob Carol (whisper) 13:30 29 January 2014 (UTC)]
Eve appears in [[177: Alice and Bob]] --[[User:JakubNarebski|JakubNarebski]] ([[User talk:JakubNarebski|talk]]) 08:14, 29 January 2014 (UTC)

Heh. I was immediately reminded of the movie, Bob & Carol & Ted & Alice. http://www.imdb.com/title/tt0064100/ I wonder if that movie influenced the encryption names, or vice versa, or mere coincidence?[[Special:Contributions/108.162.216.72|108.162.216.72]] 12:31, 29 January 2014 (UTC)

I think the explanation looks complete to me. I vote to remove the tag. [[User:Jarod997|Jarod997]] ([[User talk:Jarod997|talk]]) 14:04, 29 January 2014 (UTC)

Removed then. There was someone who asked for more [[Cryptography]] comic references. I found 14 and have thus made a new category (see link below). Feel free to add more if I have not found them all by searching on Cryptography and Encryption (I have only included those where there were some direct mention of these issues in the commic - or title text) and not just because there was mention of it in the explanation. However, the words does not have to appear in the commic before I included them. i.e. [[PGP]]. But also feel free to delete one from the list if I was too quick to include it [[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 15:45, 29 January 2014 (UTC)

The description misses a key aspect of the comic. The conversation follows the pattern of a message being sent from Cueball to the Computer Scientist, with the CS sending an acknowledgement back and Cueball continuing --- much in the matter of an internet communication protocol, as referenced in the title. [[User:JamesCurran|JamesCurran]] ([[User talk:JamesCurran|talk]]) 17:06, 29 January 2014 (UTC)

I added a bit of text regarding the possible extra joke in the comic title. [[Special:Contributions/108.162.219.125|108.162.219.125]] 03:01, 18 February 2015 (UTC)

Really excellent explanation. Complete, concise and well written, with some helpful notes in the comments. Keep up the good work! [[Special:Contributions/108.162.219.58|108.162.219.58]] 18:43, 29 January 2014 (UTC)

I agree this would explain the protocol title, but how does it compute with the message at the bottom: ''I've discovered a way to get computer scientists to listen to any boring story''? [[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 18:55, 29 January 2014 (UTC)
:The point is that Cueball tells a completely mundane and booooring! story (might be last evening's soap opera, for example), but by replacing the protagonist names with Alice, Bob and Eve, names commonly used in explanation of public key cryptography, he tricked the Computer Scientist into believing he describes some cryptography protocol, thus making him interested. [[User:Edheldil|Edheldil]] ([[User talk:Edheldil|talk]]) 10:22, 31 January 2014 (UTC)
::By the way, what Cueball describes might very well be DNS cache poisoning -- or what NSA's supposed FOXACID servers do. [[User:Edheldil|Edheldil]] ([[User talk:Edheldil|talk]]) 10:31, 31 January 2014 (UTC)

I believe the essence of this story is in the encryption aspect, not the TCP. Many protocols feature a message-and-reply type of structure, it's not unique to TCP. The alternative to having CS reply to each phrase is to have him not reply to each phrase, which would be boring and not really indicate what's going on in CS's head. As some cryptography problems can be complex they are sometimes stated in "chunks" so people can follow along [https://en.wikipedia.org/wiki/Dining_cryptographers_problem more easily] (See the Description section of the link). In trying to follow what might be a complex problem sometimes people will acknowledge that they understand each part in turn - weather for their own benefit or that of the problem stater. [[User:Jarod997|Jarod997]] ([[User talk:Jarod997|talk]]) 21:04, 29 January 2014 (UTC)
:Found it: [https://en.wikipedia.org/wiki/Bruce_Schneier Bruce Schneier], a notable modern Cryptographer has published a number of cryptography books in which he routinely references characters such as Alice, Bob, and Eve. [[User:Jarod997|Jarod997]] ([[User talk:Jarod997|talk]])
:Also: TCP/IP doesn't necessarily ack every packet, it can also ack multiple packets in one go. This allows for a much larger throughput as the latency per packet goes down to zero. [[User:Kaa-ching|Kaa-ching]] ([[User talk:Kaa-ching|talk]]) 09:33, 30 January 2014 (UTC)

Sometimes I like thinking about archaeologists in the far future, digging through the ruins of the second dark age, and finding one of these. They may have no idea what it says, or what it's about. But if they have any sense of humor, their laughs will cause the world to crack and cumble. Cities will collapse as the vibrations echo through the planet which we so conveniently hollowed out. The world will collapse in on itself. Whoever is on the moon or wherever will look on in horror as the planet itself seems to crumble like that of a supernova. XKCD will be the death of us all. {{unsigned|DollarStoreBa'al|20:58, 18 December 2024}}

Welp, i've got to the point where im so much of un undertale yellow fan that the ost just played while i was reading this.

Talk:590: Papyrus/Font

2025-05-08T06:23:58Z

162.158.162.103:

I feel so papyrus [[User:CalibansCreations|'''<span style="color:#ff0000;">Caliban</span>''']] ([[User talk:CalibansCreations|talk]]) 08:51, 8 January 2025 (UTC)

I can't believe this is the only page that is not categorized. .-. Category:Jokes would be fine :) --[[User:1234231587678|1234231587678]] ([[User talk:1234231587678|talk]]) 03:07, 18 March 2025 (UTC)
:Funnily enough, before I fixed it (see history), this page was categorised as a comic so we had one more comic in the categories. --[[User:FaviFake|FaviFake]] ([[User talk:FaviFake|talk]]) 15:44, 18 March 2025 (UTC)
NYEH HEH HEH!
(and yes i know undertale came out in 2015 and i dont care)