If heat transfer happens reversibly, which property of the working substance undergoes a corresponding change_________________?
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Answer: D. entropy
Explanation
Entropy is defined as the integral of reversible heat transfer divided by temperature. Any reversible heat addition or removal directly alters this property. It serves as the definitive state variable quantifying thermal energy unavailability. Clausius introduced entropy to measure thermal energy dissipation within systems. State properties depend only on the current condition, not the historical path. Reversible interactions ensure no extra entropy is generated by internal friction.
Power generation cycles utilize entropy to evaluate component efficiencies. Refrigeration systems monitor entropy changes to optimize cooling performance. Chemical engineers track entropy to determine the feasibility of spontaneous reactions. Option A temperature changes during heat transfer but is not the sole property. Option B enthalpy changes but depends heavily on pressure work components. Option C internal energy changes with heat and work, not heat alone.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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