What is the Rate of Entropy Production from Heat Leakage in a House?

AI Thread Summary
The discussion revolves around calculating the rate of entropy production due to heat leakage from a house, where heat escapes at a rate of 2.5×10^4 kcal/h. The temperatures inside and outside the house are 21°C and -5°C, respectively. The initial calculations yield an incorrect entropy production rate of 2.29 cal/(K·s), while the correct answer is 8.2×10^3 cal/(K·h). The discrepancy arises from a misunderstanding of unit conversions, highlighting the importance of careful attention to units in thermodynamic calculations. Proper unit conversion is crucial for obtaining accurate results in entropy calculations.
Bill Foster
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Homework Statement



Heat leaks out of a house at the rate of 2.5\times{10^4} \frac{kcal}{h}. 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.


Homework Equations



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})}


The Attempt at a Solution



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

T_1=21°C=294.15K
T_1=-5°C=268.15K

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

The answer in the back of the book is 8.2\times{10^3}\frac{cal}{K\times{s}}.
 
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If you leave your answer in cal/(K x h), you get the book's answer. Maybe they made a mistake?
 
Now I feel stupid for overlooking a such a trivial detail as unit conversions.
 
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