Water at a temperature of 15°C produces ice cubes at a temperature of −5°C. Water is taken in at the
rate of 1 kg every 7 minutes and the input power to the machine is 300 W. The specific heat capacity of
water is 4187 Jkg−1K
−1, the specific heat capacity of ice is 2100 Jkg−1K
−1 and the specific latent heat of
fusion is 335 Jkg−1
i) Calculate the heat energy extracted per kg of ice produced
This part of the task provides the remaining evidence for the grading criterion P8.
ii) Calculate the thermal efficiency of the ice making machine.
This part of the task provides the evidence for the grading criterion M3.