An electric iron has a power of 1200 W. It transfers 360 000 J360\,000\ \text{J}360000 J of energy while it is switched on.
Use the equation E=PtE=PtE=Pt.
Calculate the time for which the iron is switched on.
State what a power of 1 W means.
Name the energy store of the soleplate that increases when the iron is switched on.
Some energy is transferred to the surrounding air.
State whether this transfer is useful or wasted.
105 exam-style questions on Edexcel GCSE Physics 10.3 Electrical energy and power, covering 10.3.1 The heating effect of an electric current, 10.3.2 Reducing energy transfer in wires, 10.3.3 Advantages and disadvantages of the heating effect, 10.3.4 Energy transferred by an electrical circuit, 10.3.5 Electrical power, and 10.3.6 Energy transfers in domestic devices. Each one has a worked solution and a mark scheme showing where the marks go.