51. Steam at 2 MPa and 250°C in a rigid cylinder is cooled until the quality is 30%. Find the heat

rejected from the cylinder.

@ 2 Mpa and 250°C: υ = 0.11144 m3

/kg u = 2679.6 kJ/kg

@ 2 Mpa, (saturated):υf = 0.0011767 m3

/kg υg = 0.09963 m3

/kg

uf = 906.44kJ/kg ug = 1693.8 kJ/kg

A. -423.23 kJ/kg

B. -926.26 kJ/kg

C. -1265.02 kJ/kg

D. 1082.34 kJ/kg