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Ayame17
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What is the maximum amount of mechanical work that can be got by a reversible engine working from a finite heat source of thermal capacity, C=1000J/K, if it is initially at 373K and the engine discharges to a bath of virtually infinite heat capacity at 273K?
[You may take C as a constant over the temperature range, 273K - 373K]
Good question...!
Well, I know that W=Q1-Q2, which is also =Q(T1-T2)/T1. I also know that W=(integral of)Pdv, and that Q=mc(deltaT). However, I can't see how to get the values for P or Q. To begin with, I'm not sure whether I should treat it as a Carnot engine, since most reversible ones are, but not all of them. And if so, should I treat the entropy (S) as 0, which might help? I worked out deltaS = Cln(T2/T1) = -312.1066, which I don't know if it is right and if it will help anyway!
Any help at all will be appreciated!
Homework Statement
What is the maximum amount of mechanical work that can be got by a reversible engine working from a finite heat source of thermal capacity, C=1000J/K, if it is initially at 373K and the engine discharges to a bath of virtually infinite heat capacity at 273K?
[You may take C as a constant over the temperature range, 273K - 373K]
Homework Equations
Good question...!
The Attempt at a Solution
Well, I know that W=Q1-Q2, which is also =Q(T1-T2)/T1. I also know that W=(integral of)Pdv, and that Q=mc(deltaT). However, I can't see how to get the values for P or Q. To begin with, I'm not sure whether I should treat it as a Carnot engine, since most reversible ones are, but not all of them. And if so, should I treat the entropy (S) as 0, which might help? I worked out deltaS = Cln(T2/T1) = -312.1066, which I don't know if it is right and if it will help anyway!
Any help at all will be appreciated!