00:01
So in this question, we've got two very large parallel plates, maintained at uniform temperatures, t1 is 600 kelvin, t2 is 400 kelvin, and they have emissivities.
00:18
One moment.
00:20
You have emissivities, epsilon 1 is 0 .5, and epsilon 2 is 0 .9.
00:28
And we want to determine the net rate of radiation heat transfer.
00:31
Well, the intensity of radiation is given by the stefan boltzmann law, which is that it's epsilon sigma t to the 4, where sigma is the stephan bolzman constant, which we can look up, and this constant is sigma is 5 .6704 times 10 to the minus 8.
01:01
And this is going to be given in watts per meter squared per, per.
01:06
Kelvin to the 4.
01:11
Okay.
01:15
So let's continue...