Consider a class room of dimensions `5 xx 10 xx 3 m^(3)` at atemperature `20^(@)C` and pressure 1 atm. There are 50 people in the room, each losing energy at an average of 150 watt. Assuming that walls ceiling, floor and furniture are perfectly insulated and none of them absorb heat, what time (in seconds) will be needed for rising the temperature of air in the room to body temperature i.e., `37^(@)C`? (For air `C_(P) = (7)/(2)R`. Loss of air to outside as the temperature rises may be neglected).

Answer

4