00:01
For this question, we're asked to find the rate of heat conduction through the fur of a large animal.
00:08
So they give us in the question that the thickness of the fur is 3 centimeters, which is 0 .03 meters.
00:18
They also tell us that the area of the fur is 1 .4 square meters.
00:24
The temperature of the skin is 32 degrees celsius.
00:28
And the temperature of the air, which is where the heat is going, is minus 5 degrees celsius.
00:35
They tell us that the thermal conductivity of the skin is the same as that of air.
00:39
So if we look that up, k of air equals 0 .03 joules per seconds times meters times degrees celsius.
00:50
And in this case, we want to use the thermal conductivity equation for the rate of heat conduction, which is q equals k times a times t2 minus t1 over d.
01:05
Okay, so part a, asks us to find q.
01:11
So we're just going to plug in k, 0 .023 joules per seconds times meters times degrees celsius, times a, which is 1 .4 square meters, times a change in temperature.
01:25
So that's 32 degrees celsius minus negative 5 degrees celsius.
01:32
And this becomes positive.
01:33
This is just adding divided by d, which is 0 .03 meters.
01:39
So our degrees celsius cancels out with this addition up top...