explain xkcd - User contributions [en]

2952: Routine Maintenance

2024-06-30T08:28:55Z

TheDesaj2: transcript for extra text on the can added (in parentheses)

{{comic
| number = 2952
| date = June 28, 2024
| title = Routine Maintenance
| image = routine_maintenance_2x.png
| imagesize = 299x413px
| noexpand = true
| titletext = The worst was the time they accidentally held the can upside down and froze all the Earth's magma chambers solid.
}}

==Explanation==
{{incomplete|Created by an ONCOMING LETHAL DUST CLOUD - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

A recommended routine maintenance step for many electronics, such as desktop computer towers, is to remove the buildup of dust on a regular basis. This bit of routine maintenance can help prevent the electrical components from overheating, and lengthen the lifetime of these electronics. There exists {{w|Gas duster|cans}} of high-pressure gas, as depicted, to blow dust out without a person blowing themselves, thus allowing them to keep their distance and not get a faceful of dust, or adding unintended moisture to the electronics.

This is suggesting that this is a maintenance step performed on the Earth itself, blowing gas into the Earth to force out the dust. However, filling the atmosphere with dust would be unhealthy and fatal to living beings, so as a safety measure everyone would have to take shelter. This is a reference to one theory about the extinction of many creatures, especially the (non-avian) dinosaurs, that a crashing meteor sent so much dust into the air that it killed off all non-avian dinosaurs in a much wider area than were directly affected by the initial impact. Those lineages that chanced to survive the global effects (including our own mammalian ancestors, and the avian dinosaurs that led to todays birds) must have been able to escape the worst of the disrupted ecosphere, perhaps some of them by already being more inclined/suited to living in burrows while the worst of the atmospheric effects subsided and let them exploit various newly vacant (and/or changed) environmental niches.

The image suggests that the "routine maintenance" for Earth would involve using the {{w|Hawaii hotspot}} (possibly <em>via</em> its most active volcano, {{w|Kilauea}}), as the point to insert the high-pressure gas, causing volcanoes to erupt in Iceland, the {{w|Aleutian Islands}} or the {{w|Kamchatka Peninsula}}, the {{w|Andes}}, and elsewhere; the two geographically-indeterminate plumes may represent Italy and Indonesia.

The title text mentions using the can upside-down, and this freezing solid the magma chambers. Pressurised canisters of air, as with similar aerosol sprayers, make use of a propellant gas that condenses into a liquid when compressed. As the can is sprayed, the release of pressure allows some of the liquid to evaporate and take the place of the released gases, become some of the gas subsequently released (or all of it, if there are no other contents required to fulfil its purpose as a spray). The propellant liquid/gas acts as a refrigerant, as its transition from dense liquid to space-filling gas requires it to 'boil off', this process needing to pick up {{w|Enthalpy of vaporization|heat (or 'enthalpy') energy}}. Under typical operation, this happens within the can itself, the heat being taken initially from the can itself as it tries to attain thermal equilibrium. As a result, the can itself (and the expelled gases) will be cooled a little as the heat 'loss' is taken from the general mass of the can, including its contents, and then (ultimately) anything touching or surrounding the slightly cooled can and its spray. This is precisely how a purposeful refrigerant acts, either as a one-time process or as a reversible cycle where repressuring a suitable gas can 'release' heat (the heat/enthalpy of condensation) at the 'hot side' of a refrigerator, leaving the system with more liquid it that it can later let boil and cool the 'cold side' of the system.

It is not normally useful for such a can to allow the liquid propellant-in-waiting to exit the container, as it would waste its usefulness as a source of pressure once it does. But by holding the container the wrong way up (which way that is being dependant upon its design, and intended use...) the pressurised contents push the liquid out via the nozzle's stream. The now exposed propellant is now free to evaporate into the air at atmospheric pressure, typically much lower than the constraints it had within the can, after landing directly upon whatever the can was sprayed at. The resulting demand for heat energy (much more rapid than normal, and likely concentrated upon a much smaller target than the can itself represents) produces a greater localised drop in temperature and can lead to freezing nearby liquids (which may or may not be intended/useful). Of course, the total 'cooling effect' of such a can does not change, depending upon how it is (mis)used, it merely changes the extent (and lifetime) of application, and how extreme the temperature change may be within a much more limited 'liberation' of its cooling ability.

Spraying canned "air" in reverse is a party trick used to very quickly cool beverages, being able to bring them down from room temperature to ice cold in seconds, if performed correctly. Some 'spray cans' are ''designed'' to let you freeze things (e.g. to help in plumbing repairs) or safely chill surfaces (e.g. for first-aid purposes), but these are exceptions (that require judicious use) and generally it is a wasteful use of a spray-can, if not actually unwise.

Given the location of the planetary-scale dust-busting 'air canister', it may be considered confusing which 'way up' is the correct orientation, given that Earth-gravity would be pulling the contents sideways (however that changes what the nozzle ends up ejecting from the can itself). But it would also have its own significant internal 'can-centric' gravity that possibly (depending upon how full of still-liquid propellant it is) exceeds that of the Moon, possibly letting all the denser liquid hold itself into the centre of the canister, even against the nearby Earth's gravity. Although, as significantly closer to the Earth, it could also be a far greater influence upon Earth's own tides (not alluded to in the comic), making the dusting of the atmosphere or the freezing of some of its magma secondary issues to the sheltering population.

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

:[The nozzle of a "Dust-Off" (compressed air) gas duster can is pointing into a hole on the Earth's surface in the Pacific Ocean around where Hawaii is located, and its trigger is pressed as an arrow indicates, resulting in dust clouds being released from five visible spots of the Earth. These eruptions can be seen in the Aleutian Islands or Kamchatka Peninsula, Iceland, the Andes, and two further in the eastern hemisphere on the other side of the Earth.]

:[Caption below the panel:]
:I know routine maintenance is important, but I hate how we all have to take shelter for 48 hours every year while they flush out the Earth's magma system for cleaning.

{{comic discussion}}

[[Category:Geology]]

2946: 1.2 Kilofives

2024-06-15T10:22:42Z

TheDesaj2: Added title text to the transcript.

{{comic
| number = 2946
| date = June 14, 2024
| title = 1.2 Kilofives
| image = 1 2 kilofives 2x.png
| imagesize = 256x342px
| noexpand = true
| titletext = 'Oh yeah? Give me 50 milliscore reasons why I should stop.'
}}

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

Abraham Lincoln's {{w|Gettysburg Address}} features the phrase "four {{wiktionary|score#Noun|score}} and seven"‍ to refer to 87 (a score refers to the number 20). Cueball (possibly representing [[Randall]]) likes the idea of unusual ways to refer to numbers so he uses a metric prefix to state the population of the town.

{{w|Metric prefix|Metric prefixes}} can be added to a unit to scale up or down its magnitude; for example, {{w|Kilo-|"kilo-"}} increases the unit's magnitude by a factor of 1,000, so a kilometer is as long as 1,000 meters. Although metric prefixes can be added to all sorts of units, they're not ordinarily added to number words to modify their magnitude{{Citation needed}}. The expression "kilofive" to mean 5,000 is therefore unusual. Such modification of magnitude can be accomplished by adding the corresponding word, for example in this case "five thousand".

Taking "kilofive" to be a unit meaning 5,000, the population of East Hills, 6,000, can therefore be expressed as 1.2 kilofives.

In the title text, Cueball has apparently annoyed White Hat with his confusing expressions of numbers, but he doubles down, now directly including the word "score". 50 milliscore, or 50 × 1&frasl;1000 × 20, would be equal to 1.

The comic might refer to the village of {{w|East Hills, New York}}. As of the 2020 census, it had a population of 7,284, or around 1.2 kilosixes.

==Trivia==
In Roman numerals, {{w|Roman_numerals#Large_numbers|symbols can be added to numerals}} to denote orders of magnitude. In this system, 1,000 might be written as CIↃ, or I with a bar above it.

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

:[Cueball, with his palm raised, is talking to White Hat. There is a sign on the ground in the background.]
:Cueball: It's a pretty small town - the population is just 1.2 kilofives.
:[The sign reads:]
:Welcome to
:<big>East Hills</big>
:Pop. 6,000

:[Caption below the panel:]
:I don't know why Abraham Lincoln should be the only one who gets to come up with weird ways to say normal numbers.

:[Title text:]
:'Oh yeah? Give me 50 milliscore reasons why I should stop.'

{{comic discussion}}

[[Category:Comics featuring Cueball]]
[[Category:Comics featuring White Hat]]
[[Category:Comics featuring real people]]

2885: Spelling

2024-01-26T10:21:43Z

TheDesaj2: Spelling correction: blag -> blog

{{comic
| number = 2885
| date = January 24, 2024
| title = Spelling
| image = spelling_2x.png
| imagesize = 281x333px
| noexpand = true
| titletext = Any time I misspell a word it's just because I have too much integrity to copy answers from the dictionary.
}}

==Explanation==
{{incomplete|Created by COPYING AND PASTING. Do NOT delete this tag too soon.}}

Search engines like Google autocorrect most misspelled words, providing the correct spelling. Some people get help with hard-to-spell words by entering their best guess into Google, then copy-pasting the correct version.

Cueball has an unusually strict interpretation of {{dict|plagiarism}} in which copying the ''individual word'' "plagiarism" without attribution would be plagiarizing, and this misplaced integrity makes him morally opposed to doing so.

He also does not consider the option to cite his source (Google Search) when including the word "plagiarism" in his document:
"plagerism - Google Search." Google, https://www.google.com/search?q=plagerism. Accessed 24 January 2024.

The title text implies that Cueball's absurdist view of plagiarism applies much more widely when he says he only ever misspells words because he has too much integrity to copy the spelling from the dictionary, an act he also considers to be plagiarism. Simply using the dictionary to spell a word correctly is not plagiarism and doesn't require a citation. Any style guide or professional editor would advise Cueball that correct spelling is much preferred to incorrect spelling or superfluous citations.

Note that while spelling assistance should not be cited, citing a dictionary can be appropriate when using the ''entry'' associated with a word, for example:
* Providing a definition: If you're using a definition from a dictionary to make a point in your writing. This is because the definition is serving as a source of evidence or support for your argument.
* Etymology or historical usage: If you are discussing the etymology or historical evolution of a word.

"Plagiarise" rather than "plagiarize" is the common spelling in many parts of the English-speaking world. Search engines may localize(/localise) the appropriate spelling(s) based on the user's (presumed) location.

A common misspelling of plagiarism is [[https://capitalizemytitle.com/plagiarize-vs-plagerize-how-do-you-spell-it/ plagerism]], perhaps because of the way the word sounds when pronounced.

==Transcript==
:[Cueball is sitting on an office chair at a desk and looking at a laptop while resting his hands on it. Megan is standing behind him and looking at the laptop as well.]
:Megan: When I can't spell a word I usually just Google and copy and paste it from the results.
:Cueball: Yeah, but I can't do that '''''here!!'''''

:[Caption below the panel:]
:Why spelling "plagiarism" is especially hard

==Trivia==
Randall had previously commented on some ''other'' problems with using Google's suggestion feature as a spellchecker in [https://blog.xkcd.com/2010/05/03/color-survey-results/ the Color Survey Results post] on the xkcd blog.

{{comic discussion}}

[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Megan]]
[[Category:Language]]