Difference between revisions of "Talk:2748: Radians Are Cursed"
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:I just hope that was Celsius degrees (or Kelvin), rather than Fahrenheit(/Rankine). ;) [[Special:Contributions/172.71.242.190|172.71.242.190]] 10:51, 11 March 2023 (UTC) | :I just hope that was Celsius degrees (or Kelvin), rather than Fahrenheit(/Rankine). ;) [[Special:Contributions/172.71.242.190|172.71.242.190]] 10:51, 11 March 2023 (UTC) | ||
::If you use Kelvin with degrees you have already lost...[[Special:Contributions/172.68.51.178|172.68.51.178]] 13:29, 11 March 2023 (UTC) | ::If you use Kelvin with degrees you have already lost...[[Special:Contributions/172.68.51.178|172.68.51.178]] 13:29, 11 March 2023 (UTC) | ||
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+ | So the volume of the sky is 4/3 π r³ = 7,092,429 cubic degrees |
Revision as of 09:58, 12 March 2023
how do transcript 172.70.127.37 19:23, 10 March 2023 (UTC)
https://en.wikipedia.org/wiki/Square_degree may be of some help with this one. 162.158.166.124 19:44, 10 March 2023 (UTC)
The comic isn't actually correct. A radian is not equal to the length of a circle's radius; it is equal to the length of the radius, multiplied by 2π, divided by the perimeter, which is why it has no units, while the length does. In other words, radian/2pi=length of radius/length of perimeter. 172.70.46.84 19:51, 10 March 2023 (UTC)
As suggested by the above Wikipedia link, square degrees are in fact often used in astronomical contexts. Also, it's quite standard to say that radian=1; see for example SI derived unit. An angle is the ratio between the arc length and the radius, and we just optionally append "radian" for clarity. So 1 = 57.3 degrees is correct; Randall simply used the wrong argument to obtain it. Aseyhe (talk) 20:57, 10 March 2023 (UTC)
- I always understood radian to be the name of the unit, so by definition 1 radian=1. Barmar (talk) 21:17, 10 March 2023 (UTC)
- It is a shame that astronomers don't use the proper unit for such things: the steradian. It is literally there for describing the 3D equivalent of angle. Oh well... --172.69.79.137 04:16, 11 March 2023 (UTC)
- It is a shame that astronomers don't use the proper for length, preferring ad-hoc units based on the solar system. But if you use a different ad-hoc unit based on the properties of the solar system they throw a hissy fit.172.70.38.150 06:51, 12 March 2023 (UTC)
Someone fix the vandalism, how do you upload images? --Purah126 (talk) 03:06, 11 March 2023 (UTC)
- I'm doing it but that user needs to be blocked.
- To revert images, scroll down and click the revert link next to the last good version.
- And do not feed the trolls. ~ Megan she/her talk/contribs 03:10, 11 March 2023 (UTC)
On reading this I vividly remembered a maths teacher once asking our class "What's 10% of a straight line?", and the looks of disgust and bewilderment when he said the answer was 18 degrees. 172.70.86.147 08:31, 11 March 2023 (UTC)
- I just hope that was Celsius degrees (or Kelvin), rather than Fahrenheit(/Rankine). ;) 172.71.242.190 10:51, 11 March 2023 (UTC)
- If you use Kelvin with degrees you have already lost...172.68.51.178 13:29, 11 March 2023 (UTC)
So the volume of the sky is 4/3 π r³ = 7,092,429 cubic degrees