Engineering Board Exam Reviewer · Thermodynamics · medium
A system receives 500 kJ of heat reversibly at a constant temperature of 400 K. What is its change in entropy?
- 0.80 kJ/K
- 200,000 kJ/K
- 1.25 kJ/kg
- 1.25 kJ/K
Answer
D. 1.25 kJ/K
Solution
S = Q/T = 500/400 = 1.25 kJ/K.
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