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

Heat leaks out of a house at the rate of [tex]2.5\times{10^4} \frac{kcal}{h}[/tex]. The temperature inside the house is 21°C and the temperature outside the house is -5°C. At what rate does this process produce entropy.

2. Relevant equations

[tex]S(A)-S(A_0)=-\frac{\Delta{Q}}{T_1}+\frac{\Delta{Q}}{T_2}=\Delta{Q}\times{(\frac{1}{T_2}-\frac{1}{T_1})}[/tex]

3. The attempt at a solution

Heat flows from the high temp res to the low temp res at a rate of [tex]2.5\times{10^4} \frac{kcal}{h} = 6944.4 \frac{cal}{s} = \Delta{Q}[/tex].

[tex]T_1=21°C=294.15K[/tex]

[tex]T_1=-5°C=268.15K[/tex]

Plugging and chugging I get: [tex]2.29 \frac{cal}{K\times{s}}[/tex], which is wrong.

The answer in the back of the book is [tex]8.2\times{10^3}\frac{cal}{K\times{s}}[/tex].

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# Homework Help: Thermodynamics: entropy

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