Question

Review To help keep her barn warm on cold days, a farmer stores 870 kg of warm water in the barn. Part A How many hours would a 3.50-kilowatt electric heater have to operate to provide the same amount of heat as is given off by the water as it cools from 20.0°C to 0°C and then freezes at 0 °C? O AEQ * 0 2 ? Submit Request Answer

Answer 1

here,

let the time taken is t

Power , P = 3.50 kW = 3500 W

m = 870 Kg

Now, heat needed = power * time

870 * (334 *10^3 + 4186 * 20 ) = 3500 * t

solving for t

t = 103833 s = 28.8 hours

the time taken is 28.8 hours for the heater