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

Two rooms, each a cube 3.8 m on a side, share a 12 cm thick brick wall. Because of a number of 100 W light-bulbs in one room, the air is at 27°C, while in the other room it is at 10°C. How many of the 100 W light-bulbs are needed to maintain the temperature difference across the wall? (Round your answer up to the nearest integer.)

2. Relevant equations

Q/t=kA(t_{1}-t_{2})/l

3. The attempt at a solution

This looks so easy and I attempt to solve it and I get it wrong.

I used

Q/t=kA(t_{1}-t_{2})/l

=(0.84J/s*m*C)(14.44m^{2})(27C-17C) / (0.12m)

=1718.36 then divide by 100 and it equals 17.1836=17

Do you have any ideas as to what I'm not comprehending because I'm sure this has to be the correct number of bulbs.

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# Homework Help: Rate of heat flow

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