Answer:
7.894 MJ
Explanation:
Given that:
The mass of the saturated water vapor = 3.7 kg
The pressure of the saturated water vapor = 0.4 MPa
From saturated properties of steam tables when the pressure is at 0.4 Mpa
The enthalpy in (kJ/kg);
hf = 604.7 kJ/kg
hg = 2738.1 kJ/kg
The rejected heat during this process is:
Q = m(hg - hf)
Q = 3.7(2738.1 - 604.7) kJ/kg
Q = 3.7(2133.4) kJ/kg
Q = 7893.58 kJ/kg
Q = 7.894 MJ