815: Mu

Explain xkcd: It's 'cause you're dumb.
Jump to: navigation, search
As the CoKF approaches 0, productivity goes negative as you pull OTHER people into chair-spinning contests.
Title text: As the CoKF approaches 0, productivity goes negative as you pull OTHER people into chair-spinning contests.

[edit] Explanation

The title of the comic, "Mu", refers to the symbol μ. This letter of the Greek alphabet is commonly used in mathematics and physics in many cases and here it denotes the coefficient of friction which describes the ratio of the force of friction between two connected bodies.

Desk chairs usually have the ability to turn and some chairs spin more easily than others. A desk chair which spins easily could be described as having a low coefficient of friction. The horizontal axis of the chart ranges from very easy to spin on the left, to very difficult to spin on the right. The comic shows that if the chair is too difficult to turn it is annoying and impacts productivity. However, if it is too low spinning one's chair becomes more fun than working.

The title text notes that if your chair spins too easily, you can actually hurt other people's productivity by spinning competitively.

In classical mechanics the angular momentum can be transferred to other objects when a rotating object does not have any friction and is rotating very fast. For example, when a reaction wheel inside a spacecraft changes its speed, it turns the entire satellite around. "None of this is intuitive" as shown in this video.

[edit] Transcript

[Cueball spins in circles on a chair next to a desk. A graph of productivity vs Coefficient of friction of desk chair shows a curve that drops off very quickly as the coefficient of friction approaches zero, with the productivity becoming negative at low values. It plateaus in the middle of the graph, and then begins to drop less steeply as coefficient of friction increases above the optimal point.]
Cueball: Wheeeeeeee
Comment.png add a comment!


I don't understand the max. Do chair-sitters decrease in productivity as mu increases because they are trying in vain to spin difficult chairs? In the limiting case of a rigid chair, do chair-sitters vainly attempt to rotate their chairs anyways? (talk) (please sign your comments with ~~~~)

I think a difficult-to-spin chair just feels uncomfortable, so it kind of subconsciously affects your productivity. In fact most people never sit completely still and often you have to turn to get something from next to your desk or move around... That can be pretty annoying to some people. The way I imagine it, this would not apply to an "infinitely" rigid chair (a simple one with four legs), because you don't expect it to move so it would still feel "right", if it's sufficiently comfortable in the other regards (softness, angle of the backrest, ...). Maybe productivity would not be as high as with an optimal spinning chair, since it would not be as much fun, but that's not in the picture anyway. Laden (talk) 03:07, 19 January 2013 (UTC)
I would think that the function approaches a fixed chair production coefficient ( ;) A set number for that chair subject to other variables which are being kept constant [as Laden pointed out]) as Mu approaches infinity.
It's most likely a peicewise function with a different value @ infinity--granted truly rigorous analysis would conclude that all chairs no matter how "rigid" would experience microscopic torques from people turning and shifting in them.
But this doesn't affect the psychology of being frustrated in a sticky swivel chair. As such that productivity would likely be higher than the CPC, which I would expect as Laden does would be to be lower than the max CPC of a swivel chair (which if I could would by now be denoting as C sub-S and rigid chairs as C sub-R)
A similar graph could likely be made for a chair which has a certain maximum "reclination"
Apologies for lack of formatting I've never commented before, and clearly was completely backwards from what I intended when i originally commented. Whoops
--Rick 20:18:~45 13-4-13 03:06, 14 April 2013 (UTC)
Rick, I hope you don't mind, I've come through and indented your comment the way I think you intended. If this is incorrect, feel free to correct it. lcarsos_a (talk) 22:33, 14 April 2013 (UTC)
Reference to electrons

I cannot shake the feeling that this comic makes a reference to the spin of electrons. However, not being a physicist, I cannot quite place the implications. Also, the graph looks quite familiar to me. --Alfons (talk) 09:50, 20 November 2013 (UTC)

Now I know, where I know this graph from: It is an inversed Morse potential. Does anybody know, whether it might have something to do with the Franck-Condon principle? --Alfons (talk) 14:56, 25 November 2013 (UTC)
Title of the comic

The title of the comic, mu (μ), is a symbol that is commonly used to denote the coefficient of friction. Posted by User:Irino..

Mu is not μ, which just means micro (one per Million). I can't see the link.--Dgbrt (talk) 17:58, 7 September 2013 (UTC)
Mu, or μ, is a Greek letter. It is often used as an abbreviation for the prefix micro-, but can also be used as a variable for the coefficient of friction. 23:04, 12 September 2013 (UTC)
Quantum mechanics

As Alfons did mention above, the graph is related to quantum mechanics. But the spin of an electron is not correct, but maybe a hint. It belongs more to this: Probability amplitude or Quantum tunnelling (the latter because of the negative values on the left.) Further investigations are needed.--Dgbrt (talk) 20:41, 25 November 2013 (UTC)

Classical mechanics
Ohh, this is a very classical mechanics comic. I must have been blind. Shame on me. Look at this angular momentum wheel: Reaction wheel. One wheel moves its momentum to an other wheel (the spacecraft in this case). This is just simple classical physics, which also not easy to understand without knowing the basics of classical mechanics. --Dgbrt (talk) 22:49, 9 December 2013 (UTC)
Personal tools


It seems you are using noscript, which is stopping our project wonderful ads from working. Explain xkcd uses ads to pay for bandwidth, and we manually approve all our advertisers, and our ads are restricted to unobtrusive images and slow animated GIFs. If you found this site helpful, please consider whitelisting us.

Want to advertise with us, or donate to us with Paypal or Bitcoin?