Saturated liquid water enters a steady state pump at P = 50 kPa. The water leaves the pump at P = 0.5 MPa. How much work is added in the pump, per kilogram of entering water?
A. 0 J/kg
B. -300. J/kg
C. 300. J/kg
D. 464. J/kg
E. Insufficient information to solve
A. Incorrect. A pressure increase requires an energy input.
B. Incorrect. You are making an algebra mistake and a conceptually flawed analysis of the system.
C. Incorrect. You cannot assume the exiting stream is saturated liquid; nothing is given to indicate it is.
D. Correct. Following Example 3-8 produces the correct work result.
E. Incorrect. There is enough information here to solve the problem using legitimate assumptions.
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