A radiator made out of a metal of specific heat capacity 450 J kg−1 K−1 has a mass of 45.0 kg and is filled with 23.0 kg of water of specific heat capacity 4200 J kg−1 K−1 .
(1) Determine the energy required to raise the temperature of the radiator–water system by 1 K.
(2) If energy is provided to the radiator at the rate of 450 W, calculate how long it will take for the temperature to increase by 20.0 °C.