An electric heater is used to heat a room of a volume 62m^3. Air is brought into the room at 5^\circ C and is changed completely twice per hour. Heat

asked 2021-02-19
An electric heater is used to heat a room of a volume \(\displaystyle{62}{m}^{{3}}\). Air is brought into the room at \(\displaystyle{5}^{\circ}\) C and is changed completely twice per hour. Heat loss through the walls amounts to approximately 850 kcal/h. If the air is to be maintainedat \(\displaystyle{20}^{\circ}\) C, what minimum wattage must the heater have? (The specific heat of air is about 0.17 kcal/kg*Co.)

Answers (1)

850 kcal/hr=850/3600(kcal/sec)= 0.236
1 kcal = 4186 J
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