Question

I stuck with this problem and the solution on our web forthisproblem post by --Craig-- seem to be the wrong (not evendoanything with the problem, I think he put wrong one). PLeasehelpme out.

An electric heater is used to heat a room of volume61m³. Air is brought into the room at 2 degree C andiscompletely replaced twice per hour. Heat loss through thewallsamounts to approximately 900 kcal/h. If the air is to bemaintainedat 25 degree C, what minimum wattage must the heater have?(Specific heat of air is about .17 kcalC/kg)

THanks.