A magnet rests on a balance. A horizontal wire is supported independently between its poles. When current flows, the balance reading increases. The current is then reversed without changing its size. Which gives the original magnetic force on the wire and the new balance reading compared with the reading at zero current?
Original force downwards; new reading lower
Original force upwards; new reading lower
Original force upwards; new reading higher
Original force downwards; new reading higher
86 exam-style questions on Edexcel GCSE Physics 12.3 The motor effect, covering 12.3.1 The motor effect, 12.3.2 Fleming's left-hand rule, 12.3.3 Force on a conductor, and 12.3.4 Electric motors. Each one has a worked solution and a mark scheme showing where the marks go.