GCSE Standard Questions: Electricity in the Home
Q8. The photo shows a coffee machine. The coffee machine uses an electric element to heat water.
(a) The coffee machine has a metal case.
Why would it be dangerous for the live wire of the electric cable to touch the metal case?
(b) The power output of the coffee machine is 2.53 kW.
The mains potential difference is 230 V.
Calculate the current in the coffee machine.
(c) The coffee machine heats water from 20 °C to 90 °C.
The power output of the coffee machine is 2.53 kW.
Given that the specific heat capacity of water is 4200 J/kg °C, calculate the mass of water that the coffee machine can heat in 14 seconds.
(Total 11 marks)