Some electricity-generating companies use a unit called the kilowatt-hour (kWh) to calculate energy bills. 1 kWh is the energy a kilowatt appliance transfers in 1 hour.
a. Show that 1 kWh is equal to 3.6 MJ.
b. An electric shower heater is rated at 230 V, 9.5 kW.
i. Calculate the current it will take from the mains supply.
ii. Suggest why the shower requires a separate circuit from other appliances.
iii. Suggest a suitable current rating for the fuse in this circuit.
c. Calculate the energy transferred when a boy uses the shower for 5 minutes.