A tank contains 125 litres of water. If it’s temperature is 20C, how long would it take for a 2kW immersion heater to raise its temperature to 60C if the average rate of heat loss is 150W?
2. Relevant equations
I am using the specific heat capacity equation:
ΔQ = mcΔT
3. The attempt at a solution
ΔQ = 125 x 4200 x 40 = 21, 000, 000 J
2kW = 2kJ per second.
Concerning Heat Loss:
2000W – 150 W = 1850 W = 1.85kW
21,000KJ = 11, 351 seconds.
11, 351 / 60 = Approximately 190 minutes.
I kind of get the feeling I’m not right. Any tips? Would be appreciated.