Engineering Board Exam Reviewer · Thermodynamics · medium
1000 kJ of heat is available from a reservoir at 1000 K. If the environment is at 300 K, what is the maximum work (exergy) obtainable from this heat?
- 700 kJ
- 300 kJ
- 1000 kJ
- 1300 kJ
Answer
A. 700 kJ
Solution
W max = Q(1 - T0/T) = 1000(1 - 300/1000) = 700 kJ.
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