Engineering Board Exam Reviewer · Thermodynamics · hard
Two Carnot engines operate in series. The first receives heat at 1000 K and the second rejects heat at 300 K. If both engines have equal efficiencies, what is the intermediate temperature?
- 547.7 K
- 650.0 K
- 461.5 K
- 500.0 K
Answer
A. 547.7 K
Solution
Equal efficiencies: 1 - T/1000 = 1 - 300/T T2 = 1000 × 300 T = 300,000 = 547.7 K.
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