(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Hi, I'm tutoring an introductory Physics class at a Big 10 school, and we've stumbled across a problem that we can't solve. Well, I thought we could solve it, but we have to use a clumsy web program to enter our answers and we can't seem to solve this one.

The problem is :

You work as an attendant in a welcome booth in Death Valley. The outside temperature is 53^{o}C. The booth has a surface area of 19m^{2}, a thickness of 0.03m, and a thermal conductivity of 11 J/s*m*K (or W/m*k). You are supplied with an air conditioner with 3000W of power that works as an ideal Carnot refrigerator. What is the minimum temperature you can have in the booth?

2. Relevant equations

[tex]\Delta[/tex]Q/[tex]\Delta[/tex]t=k*A*[tex]\Delta[/tex]T/d

OR

W=k*A*[tex]\Delta[/tex]T/d

3. The attempt at a solution

This *seems* straight forward. I've been wracking my head over this and can't seem to come up with an acceptable, much less reasonable solution.

Ideal carnot refrigerator means all power available to the air conditioner is available for cooling (the answer would be even more ridiculous if it wasn't)

So, using the second equation given below, we can set our 3000W air conditioner equal to the rest of the equation...which is all given to us except the minimum temperature, which we are trying to find. It seems straightforward, but when everything is all plugged in and done, you get a [tex]\Delta[/tex]T of.430622 and thus a minimum temperature of 52.5694^{o}C

I would hate to be that attendant! The computer program also doesn't like it either. I feel like there is a glaring error in my logic that I just can't pick up. This is due for them @ midnight on Wednesday, so I'll be thinking about it until then.

Any help would be greatly appreciated

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# Homework Help: Heat Transfer and Power

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