Question

A house with a floor area of 200 m² and a 3 m height is heated from 10°C to 22°C by an electric heater, and some air escapes through the cracks as the heated air in the house expands at constant pressure. Determine the amount of heat transfer to the air and its cost at the unit cost of$0.075/kWh. Note that 1 kWh = 3600 kJ. Assume: Air as an ideal gas with constant specific heats at room temperature. R = 0.287 kPa.m³/(kg.K) Cp = 1.007 kJ/kg.°C. The pressure is constant at 101.3 kPa.

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