Answer:
option C
option A
Explanation:
Enthalpy gained by air= 1023-290
= 733 kJ/kg
Rate of energy gain= mass flow rate × Enthalpy gained by air
= 0.1 × 733
= 73.3 kJ/s
rate of heat transfer between compressor and air= 77kW
Heat loss by air to surroundings= 77-73.3
=3.7kW
Enthalpy lost by steam in turbine= 1407.6-1236.4
= 171.2 Btu/lb
Rate of energy transfer to turbine= Enthalpy lost by steam× mass flow rate
= 171.2×5
= 856 Btu/s
Net rate of energy transfer to turbine=rate of Energy transfer to turbine- rate of heat transfer to turbine
= 856-40
= 816 Btu/s
