A gas is heat ed in a duct as it flows over a resistance heater. Consider a 101 kW electric heat ing syst em. The gas ent ers the heat ing section of the duct at 100 kPa and 27 C with a volume flow rate of 15 m /s. If heat is lost from the gas in the duct to the surroundings at a rate of 51 kW, the exit temperature of the gas is (Assume constant pressure, ideal gas, negligible change in kinetic and potential energies and constant specific heat: Cp = 1 kJ/kg. K; R = 0.5 kJ/kg K).

A gas is heat ed in a duct as it flows over a resistance heater. Consi

1.	A gas is heat ed in a duct as it flows over a resistance heater. Consider a 101 kW electric heat ing syst em. The gas ent ers the heat ing section of the duct at 100 kPa and 27 C with a volume flow rate of 15 m /s. If heat is lost from the gas in the duct to the surroundings at a rate of 51 kW, the exit temperature of the gas is (Assume constant pressure, ideal gas, negligible change in kinetic and potential energies and constant specific heat: Cp = 1 kJ/kg. K; R = 0.5 kJ/kg K).
A.	37 C
B.	76 C
C.	53 C
D.	32 C
Answer» E.

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