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		<updated>2026-04-17T08:39:58Z</updated>
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	<entry>
		<id>https://www.explainxkcd.com/wiki/index.php?title=Talk:2983:_Monocaster&amp;diff=350252</id>
		<title>Talk:2983: Monocaster</title>
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				<updated>2024-09-10T09:44:38Z</updated>
		
		<summary type="html">&lt;p&gt;172.69.194.122: &lt;/p&gt;
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&lt;div&gt;&amp;lt;!--Please sign your posts with ~~~~ and don't delete this text. New comments should be added at the bottom.--&amp;gt;&lt;br /&gt;
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Unicycles aren't (or at least aren't usually) chain-driven. I might try to fix that if my phone stops being so slow that it feels like I'm using a 90s PC to do this. Maybe a restart will help. Rebooting in 10, 9, 8... [[Special:Contributions/172.70.91.76|172.70.91.76]] 07:46, 10 September 2024 (UTC)&lt;br /&gt;
:I just went in and Actual Citation Needed it (seeing lower comment, when editor reloaded this page for me, forcing me to rewrite, that may have changed now).&lt;br /&gt;
:*It doesn't look like a chain-drive. Could be hub-geared, but not the same thing.&lt;br /&gt;
:*Chain-drive to raise the rider (most of the mass) up higher will ''raise'' the CoG.&lt;br /&gt;
:*'Underslung' chain-drive (see 1880s example, [[1673: Timeline of Bicycle Design|here]]?) has problems. Pedals hitting the ground would be one of them, unless your wheel was indeed significantly larger...&lt;br /&gt;
:*...and if it is (perhaps for better off-roading?), this intrinsically pushes up the CoG. Perhaps you are trying to lower it slightly, again, then. But you can't bring the saddle (and crotch!) lower than the now higher top of the wheel. (&amp;quot;Timeline of Bicycles&amp;quot; version excepted, assumed assymetric? In [https://digitalcollections.nypl.org/items/510d47de-4b7d-a3d9-e040-e00a18064a99 some manner]?)&lt;br /&gt;
:Add to that a few niggles about the bicycle. Not sure if intended to be a Moulton-style one (wheels maybe the classic 17&amp;quot;, frame totally wrong) or a roadbike-style-ish one (frame relatively Ok, as drawn by someone not fully adhering to the design, maybe confused by some MTB variations, but clearly not in the ~27&amp;quot; wheel range, give or take). Of course, wheels are neither concentric nor circular, so depends a bit on which bits of the 'circles' are right for the intended arc and which bits ended up more casually doodled. [[Special:Contributions/172.70.91.99|172.70.91.99]] 08:51, 10 September 2024 (UTC)&lt;br /&gt;
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Hmm, Randall missed an opportunity to put a Penny-Farthing in there... though I'm not sure how that would have categorised given that it has two wheels of different sizes. --[[Special:Contributions/172.68.205.178|172.68.205.178]] 08:19, 10 September 2024 (UTC)&lt;br /&gt;
:He has a &amp;quot;Big Wheel Trike&amp;quot; (child's low-rider style thing) in there. On the logarithmic scale, and imprecise reference point (bottom/middle(/CoG,where different)/top of wheel/vehicle/rider/whole?), both the big front wheel and the small trailing wheels colpd be in the right place-ish, although having it slightly inclined could put them in the (place Tandall considers to be) ''exactly'' right place. ((Note also where the 10(?)-wheeler truck-and-trailer is placed horizontally vs the possibly relevent &amp;quot;number of wheels&amp;quot;.))&lt;br /&gt;
:You could do something similar with the Old Ordinary (i.e. &amp;quot;Penny-Farthing&amp;quot;), either make it roughly right or depict going up a ''marginally'' steeper hill. [[Special:Contributions/172.69.194.142|172.69.194.142]] 09:04, 10 September 2024 (UTC)&lt;br /&gt;
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Re: unicycles, the COG thing doesn't look right either, but I was distracted by a (thankfully) now-deleted troll comment before and actually fixing the description is beyond my skills, especially on so little sleep.[[Special:Contributions/172.69.43.184|172.69.43.184]] 08:35, 10 September 2024 (UTC)&lt;br /&gt;
:i had good intentions, we need to call randall out --[[Special:Contributions/172.69.194.122|172.69.194.122]] 09:44, 10 September 2024 (UTC)&lt;br /&gt;
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As a unicyclist myself, I don't think the unicycle is easier to balance because of a lower center of mass and a chain drive. As a few others have mentioned, they don't normally have a chain drive, although there are a few specialist ones that do. Normally, the cranks are just attached to the hub so you can directly control the speed of the wheel at a 1 to 1 ratio, which makes it easier to balance on. The other thing that would make the unicycle easier than the monocaster is that you can control what direction the wheel is pointing by turning the seat with your thighs. [[Special:Contributions/172.68.186.128|172.68.186.128]] 09:22, 10 September 2024 (UTC)&lt;/div&gt;</summary>
		<author><name>172.69.194.122</name></author>	</entry>

	<entry>
		<id>https://www.explainxkcd.com/wiki/index.php?title=2614:_2&amp;diff=350027</id>
		<title>2614: 2</title>
		<link rel="alternate" type="text/html" href="https://www.explainxkcd.com/wiki/index.php?title=2614:_2&amp;diff=350027"/>
				<updated>2024-09-06T00:44:10Z</updated>
		
		<summary type="html">&lt;p&gt;172.69.194.122: Undo revision 350017 by 172.69.130.18 (talk) That's not how it's done. And, lacking reasoning for both, am also assuming was not even serious.&lt;/p&gt;
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&lt;div&gt;&amp;lt;noinclude&amp;gt;:''This page refers to the comic named &amp;quot;2&amp;quot;. For comic #2, see [[2: Petit Trees (sketch)]].''&amp;lt;/noinclude&amp;gt;&lt;br /&gt;
{{comic&lt;br /&gt;
| number    = 2614&lt;br /&gt;
| date      = May 2, 2022&lt;br /&gt;
| title     = 2&lt;br /&gt;
| image     = 2.png&lt;br /&gt;
| titletext = It's like sigma summation notation, except instead of summing the argument over all values of i, you 2 the argument over all values of 2.&lt;br /&gt;
}}&lt;br /&gt;
&lt;br /&gt;
==Explanation==&lt;br /&gt;
&lt;br /&gt;
This demonstrates the different ways in which the number 2 can be typeset in various scientific fields.  While these ways of typesetting are used with any number, using the number 2 in this instance provides a clear illustration how adding numbers can significantly alter a feature of a concept (such as the number of electrons in an atom) or perform a mathematical operation on it (such as raising a value to its second power).&lt;br /&gt;
&lt;br /&gt;
The dotted box represents any character (a number, letter, or bigram of letters, as appropriate to the various signifiers). All the other notation consists only of the digit 2, with occasional additional punctuation, in various locations in relation to this character. Each of these is labelled as to what its 'purpose' might normally be with respect to the general term:&lt;br /&gt;
;Regular Math&lt;br /&gt;
:Precedes the term. &amp;quot;2x&amp;quot; indicates two times the value of ''x'' in normal {{w|algebra|algebraic}} use that should be familiar for many people.&lt;br /&gt;
;Physics&lt;br /&gt;
:A preceding superscript. &amp;quot;&amp;lt;sup&amp;gt;2&amp;lt;/sup&amp;gt;H&amp;quot; would indicate the particular {{w|isotope}} of hydrogen with the atomic weight of two, namely deuterium, which is most often encountered when working with the atomic level of matter where the total number of neutrons and protons in the atom is important. It can also represent {{w|tetration}}, which is iterated exponentiation.&lt;br /&gt;
;Chemical Physics&lt;br /&gt;
:A preceding subscript, as in &amp;quot;&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt;He&amp;quot;, indicates the atomic number of an atom, which is the number of protons it contains. It is thus a guide to the number of electrons its unionised form usually has and hence is meaningful for its potential chemical interactions with other atoms. This number of protons should be invariant for any particular named element, but is usually given simultaneously with the presuperscripted mass number for which it can indicate the applicable nuclear physics. {{w|Chemical physics}} is a subdiscipline of physics and chemistry. It can also represent {{w|pentation}}, which is iterated tetration.&lt;br /&gt;
;Regular Math or Footnotes&lt;br /&gt;
:A trailing superscript is typical of a {{w|Exponentiation|power value}}; in this case &amp;quot;x²&amp;quot; would be ''x'' multiplied by itself - a common mathematical standard.&lt;br /&gt;
:Additionally, superscripted numbers are one common way to mark words in a line of text in a way to refer to a {{w|Note (typography)|footnote}}, typically placed at the bottom of the page and containing additional information that would distract from the main text itself. The ambiguity between footnotes and exponents was used in [[1184: Circumference Formula]].&lt;br /&gt;
;Chemistry&lt;br /&gt;
:A trailing subscript is used in chemistry to indicate a multiple of the element (or group of elements, in brackets) in a {{w|chemical formula}}. &amp;quot;H&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt;O&amp;quot; indicates two hydrogen atoms bond with a single oxygen atom in a molecule of water. &lt;br /&gt;
;Matrices! (&amp;quot;2,2&amp;quot;)&lt;br /&gt;
:Extending the trailing subscript with a comma-separated value usually indicates a multidimensional array (e.g., establishing a 2-by-2 square of numbers, or this particular position in such an array), which is in the realm of {{w|Matrix (mathematics)|matrix mathematics}}. This is a little bit beyond 'everyday algebra' for many people, as seemingly indicated by the exclamation of the mere mention of matrices.&lt;br /&gt;
;The Physicists Are At It Again (&amp;quot;2;2&amp;quot;)&lt;br /&gt;
:This label encompasses a mark that turns the prior comma into a semicolon, as part of the trailing subscript. This is a common notation for the {{w|Covariant derivative}} of a tensor field, which is commonly used in the mathematics of general relativity.&lt;br /&gt;
;Either High School Math Function or Incomprehensible Group Theory&lt;br /&gt;
:The number 2 in parentheses that follow a term would normally be the argument to a {{w|Function (mathematics)|function}}. For example, &amp;quot;f(2)&amp;quot; means that you should take the value 2, and find the result if manipulated by the predefined function ''f''. It is generally taught as part of algebraic mathematics in {{w|Secondary school|high school}}.&lt;br /&gt;
:In {{w|group theory}}, however, the number 2 in parentheses could indicate a special kind of group, such as an element of a symmetry group that keeps 2 fixed, or some kind of group of 2x2 matrices. For instance, {{w|SU(2)}} is a 3-dimensional {{w|Lie group}} of {{w|unitary matrices}}. These concepts are taught in graduate or advanced undergraduate mathematics courses.&lt;br /&gt;
;Oh no. Whatever this is, it's cursed.&lt;br /&gt;
:A symbol centered underneath another larger symbol is normally reserved for doing summations or products, where the big symbol is &amp;amp;Sigma; or &amp;amp;Pi;, or some other operation applied to a sequence of numbers. It does not make sense to have a single number on top of a smaller one. As with [[2529: Unsolved Math Problems|other things]] where something appears to have gone wrong in Randall's comic universe, the explanation for this particular anomaly is that it is 'Cursed'.&lt;br /&gt;
:Two {{w|natural number}}s may be stacked directly on top of one another in parentheses as {{w|binomial coefficient}}s: ( &amp;lt;table style=&amp;quot;display: inline-table; line-height: 0.6em; vertical-align: middle; font-size:7pt; text-size-adjust: none;&amp;quot;&amp;gt;&amp;lt;tr&amp;gt;&amp;lt;td&amp;gt;2&amp;lt;/td&amp;gt;&amp;lt;/tr&amp;gt;&amp;lt;tr&amp;gt;&amp;lt;td&amp;gt;2&amp;lt;/td&amp;gt;&amp;lt;/tr&amp;gt;&amp;lt;/table&amp;gt;), but those are always the same size, denoting a {{w|combination}}. In this case, ''2 choose 2'' is equal to one combination.&lt;br /&gt;
:The usage mentioned in the title text is an operation (e.g. &amp;amp;Sigma; for summation) over a variable, usually indicated by a letter such as i, where the operation is performed over all values of the variable (i.e., you &amp;amp;Sigma; (sum) the argument over all values of i). In the &amp;quot;2&amp;quot; case, the title text says &amp;quot;you 2 the argument over all values of 2&amp;quot; (i.e., the &amp;amp;Sigma; operation has been replaced by the &amp;quot;2&amp;quot; operation and the i variable has been replaced by the &amp;quot;2&amp;quot; variable). 2 is usually not an operation, though the definition of 2 under {{w|Church_encoding#Church_numerals|Church encoding}} is a function that takes in and produces functions. 2 applied to 2 in Church encoding is 4. However, the title text implies that 2 is treated like a variable, which it is not (and it's definitely not a operator and variable at the same time).&lt;br /&gt;
: Things being cursed is a common trope within recent xkcd comics, which have mentioned items including [[2332:_Cursed_Chair|Cursed chairs]] and [[:Category:Cursed_Connectors|cursed connectors]]. This notation is one of the few occasions where the supernatural has demonstrable implications for science and mathematics for those foolhardy enough to use it.&lt;br /&gt;
&lt;br /&gt;
==Transcript==&lt;br /&gt;
:[An apparent generalisation of a scientific expression consisting of a dotted rectangular 'box' outline, left empty, and various commonly-themed symbology around it:]&lt;br /&gt;
&lt;br /&gt;
:[as normal text, to the left of all the rest:] 2&lt;br /&gt;
:[superscript to the immediate left of the box:] 2&lt;br /&gt;
:[subscript also to the immediate left of the box:] 2&lt;br /&gt;
:[superscript to the immediate right of the box:] 2&lt;br /&gt;
:[subscript also to the immediate right of the box:] 2;2 [i.e. separated by a semicolon]&lt;br /&gt;
:[as normal text, to the right of almost all the rest:] (2) [i.e. enclosed in standard parentheses]&lt;br /&gt;
:[smaller subscript, centered immediately beneath the 2 within the parentheses:] 2&lt;br /&gt;
&lt;br /&gt;
:[Further details are drawn in grey tone, around or near various of the elements of the expression:] &lt;br /&gt;
;[Captions above the numbers]&lt;br /&gt;
:[with an arrow pointing to the leftmost 2:] Regular Math&lt;br /&gt;
:[with an arrow pointing to the leftwards superscript 2:] Physics&lt;br /&gt;
:[with an arrow pointing to the rightwards superscript 2:] Regular math or footnotes&lt;br /&gt;
:[with an arrow pointing to the parenthetical 2 at the right:] Either high school math functions or incomprehensible group theory&lt;br /&gt;
&lt;br /&gt;
;[Captions below the numbers]&lt;br /&gt;
:[with an arrow pointing to the leftwards subscript 2:] Chemical Physics&lt;br /&gt;
:[with an arrow pointing to just the rightwards subscript 2:] Chemistry&lt;br /&gt;
:[with an arrow pointing to a distorted grey ring snaking around only the comma of the semicolon and the following 2 of the rightmost subscript:] Matrices!&lt;br /&gt;
:[with an arrow pointing to a larger grey ring that passes fully around the whole semicolon and final 2 of the rightmost subscript:] The physicists are at it again&lt;br /&gt;
:[with an arrow pointing to the small 2 placed below the parenthetical 2:] Oh no. Whatever this is, it's cursed.&lt;br /&gt;
&lt;br /&gt;
{{comic discussion}}&lt;br /&gt;
[[Category:Math]]&lt;br /&gt;
[[Category:Physics]]&lt;br /&gt;
[[Category:Chemistry]]&lt;br /&gt;
[[Category:Comics with cursed items]]&lt;br /&gt;
[[Category:Footnotes]] &amp;lt;!-- Reference to the possibility of there being one... --&amp;gt;&lt;/div&gt;</summary>
		<author><name>172.69.194.122</name></author>	</entry>

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