Timeline for Why divide total insolation by $4$?
Current License: CC BY-SA 4.0
7 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Mar 6, 2021 at 10:02 | comment | added | Ken Fabian | Radiant heat, not conducted heat; not sure temperature is the correct unit. Watts per square metre? A quarter of a Fahrenheit temperature won't be a quarter as hot btw. | |
| Mar 6, 2021 at 10:00 | comment | added | User123 | @LeonHiebert No, fast rotation is needed only to heat a sphere uniformly. If the rotation is slower, one hemisphere of a sphere gets warmer and the other one colder. (And opposite after $P/2$.) | |
| Mar 6, 2021 at 1:32 | comment | added | uhoh | @LeonHiebert roasting is a nonlinear process; it involves a threshold. Heat diffusion is basically a linear process, though blackbody radiation is of course very nonlinear, being $T^4$. Your question turns out to be quite interesting! | |
| Mar 5, 2021 at 22:37 | comment | added | Leon Hiebert | Are you suggesting the "4" is dependent on rotation speed? | |
| Mar 5, 2021 at 22:13 | comment | added | User123 | Imagine this: $dt$ of the time on one side, $dt$ on the opposite. So half of the time $2dt$ is on one side, same on another. Now add these small amounts of time. | |
| Mar 5, 2021 at 22:09 | comment | added | Leon Hiebert | Imagine roasting 200lb pig on a spit over a fire. It takes 24hrs on a slow rotation to cook the pork evenly. The temperature is 160F. If I use your equation, and four sources of 40F surround the pig instead of a fire, the pork will still be raw. Averaging temperature serves no purpose. Further, (1−a)Ω4 suggests all sunlight is reaching the earth at the same time. This is not the case. Why not (1−a)Ω2? | |
| Mar 5, 2021 at 21:44 | history | answered | User123 | CC BY-SA 4.0 |