Q2 Two 400W fans are switched on in a perfectly-insulated, closed room at atmospheric

pressure and a temperature of 18°C. If the fans operate continuously and the room is

5m x 6m with 3.5m high ceiling. Assuming that the specific gas constant and specific

heat capacity of air at a constant volume are 287 J/kg.K and 717 J/kg.K respectively:

(a) Calculate the temperature of the air in the room after 2 hours, stating all of the

assumptions made.

[15/20 marks]

(b) What would be the temperature of the room if there was a heat loss through the

walls of 750 W throughout the two hours?

[5/20 marks]