The electric heating systems used in many houses consist of a simple duct with resistance heaters. Air is heated as it flows over resistance wires. Consider a 15-kW electric heating system. Air enters the heating section at 100 kPa and 17C with a volume flow rate of 150 m/min. If heat is lost from the air in the duct to the surroundings at a rate of 200 W, determine the exit temperature of air. Assume the air has constant specific heats. out = 200 W T2= ? W ein T = 17C P = 100 kPa 15 kW , = 150 m/min