Carnot Heat Engine: Solve for Heat Expelled to Cold Res.

AI Thread Summary
A Carnot engine operates between a hot reservoir at 63°C and a cold reservoir at -14°C, absorbing 590 J of heat. The temperatures are converted to Kelvin, resulting in T_H = 336 K and T_C = 259 K. The heat expelled to the cold reservoir is calculated using the ratio Q_H/Q_C = T_H/T_C, leading to Q_C = 504 J initially. However, the correct cold reservoir temperature should be -14°C, which is 259 K, not 287 K. This oversight in temperature conversion resulted in an incorrect calculation of the heat expelled.
tehjojo
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Homework Statement



Consider a Carnot engine that operates between a hot reservoir at 63°C and a cold reservoir at -14°C. In running 25 minutes, this engine absorbs 590 J of heat from the hot reservoir.

How much heat does it expel to the cold reservoir?

Homework Equations


Q_H/Q_C = T_H/T_C

The Attempt at a Solution


T_H = 336k
T_C = 287k
Q_H/Q_C = T_H/T_C \longrightarrow 590/Q_C = 336/287
Solving for Q_C I get 504 J, however, this is not the correct answer. What am I missing?
 
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Are you sure Tc= 287 K? The cold reservoir is at -14 C
 
Wow. It happened that on the site my homework is on, the negative sign and the number were on different lines, so I totally missed it. Thank you very much.
 
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