AP Physics 2hardmcq1 pt
A Carnot engine's efficiency approaches 100% only if
A.the cold reservoir temperature approaches absolute zero
B.the hot reservoir is cold
C.no fuel is used
D.the engine is large
Explanation
Core Concept
e = 1 − TC/TH → 100% only as TC → 0 K, which is unreachable.
Correct Answer
Athe cold reservoir temperature approaches absolute zero
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