(a)
The change in entropy of the cold reservoir.
(a)
Answer to Problem 42PQ
The change in entropy of the cold reservoir is
Explanation of Solution
Write the expression for the change in entropy.
Here,
Conclusion:
Substitute
Therefore, the work done on the gas is
(b)
The heat transferred when a monoatomic carbon gas undergoes a constant pressure process.
(b)
Answer to Problem 42PQ
The heat transferred when a monoatomic carbon gas undergoes a constant pressure process
is
Explanation of Solution
Write the expression initial temperature from ideal gas equation.
Here,
Write the expression final temperature from ideal gas equation.
Here,
Write the expression for the heat transfer.
Here,
For monoatomic gas,
Use (I), (II),(IV) to rewrite (III).
Conclusion:
Substitute
Therefore, the heat transferred when a monoatomic carbon gas undergoes a constant pressure process is
(c)
The change in entropy.
(c)
Answer to Problem 42PQ
The change in entropy is
Explanation of Solution
Write the expression for change in entropy.
Here,
Use (I) and (II) to rewrite (VI).
Conclusion:
Substitute
Therefore, the coefficient of performance of an ideal heat pump is
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Chapter 22 Solutions
Physics for Scientist and Engineers (Foundations And Connection; Volume I and II) LLF edition
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