A straight conductor in a magnetic actuator lies at right angles to the magnetic field of a permanent magnet. The table shows two tests. Between the tests, only the directions of the current and magnetic field are changed. The current magnitude, magnetic field strength and length of conductor within the field remain constant.
| Test | Direction of conventional current | Direction of magnetic field | Magnetic force on conductor |
|---|---|---|---|
| 1 | left to right | vertically upwards | 0.42 N towards the front of the actuator |
| 2 | right to left | vertically downwards | not measured |
The permanent magnet is rigidly fixed to the casing of the actuator.
Describe the magnetic force exerted by the conductor on the permanent magnet in test 2. Explain how you determine the force's direction and why the permanent magnet remains stationary.
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.