Engineering Board Exam Reviewer · Thermodynamics · medium
One kilogram of air at 300 K is compressed isothermally from 100 kPa to 500 kPa. What is the magnitude of the work required? (R = 0.287 kJ/kg· K)
- 138.57 kJ
- 430.50 kJ
- 60.18 kJ
- 344.40 kJ
Answer
A. 138.57 kJ
Solution
W = mRT (P2/P1) = 0.287(300) 5 = 138.57 kJ (work input).
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