Entropy change during a reversible adiabatic process is_________________?
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Answer: C. zero
Explanation
A reversible adiabatic process involves zero heat transfer with the external environment. Entropy change is defined mathematically as the reversible heat transfer divided by temperature. Since heat transfer is zero, the resulting entropy change is precisely zero. Adiabatic processes occur without any heat entering or leaving the system. Reversible processes involve no internal dissipation, friction, or irreversibilities. An isentropic process is defined as a process where entropy remains constant.
Idealized turbine and compressor stages are frequently modeled as isentropic processes. Engineers use the constant entropy assumption to calculate maximum possible work output. Reversible adiabatic lines appear prominently on temperature entropy thermodynamic diagrams. Option A is incorrect because entropy does not reach any maximum value. Option B is incorrect because entropy does not reach any minimum value. Option D is wrong because entropy change is predictable and exactly zero.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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