An insulated tank contains 20 kg of liquid water at the ambient condition of 100 kPa and 25oC. An internal electric heater is turned on, which consumes 20 kW of electric power. Determine the rate of change of
(a) temperature (dT/dt) and
(b) rate of change of energy (dΦ/dt) of the water in the tank.
(c) How do you explain the fact that the rate of energy increase is much less than the rate of energy transfer into the system?