A student investigates the physics of a moving-coil loudspeaker.
What type of electrical supply must be connected to the coil of the loudspeaker to produce a continuous sound wave?
Explain how this electrical supply causes the speaker cone to vibrate and produce sound.
The student designs an experiment to investigate how the force on the loudspeaker coil depends on:
The student obtains the following results:
| Magnetic flux density (T) | Current (A) | Force (N) |
|---|---|---|
| 0.15 | 0.5 | 0.06 |
| 0.30 | 1.0 | 0.24 |
| 0.45 | 1.5 | 0.54 |
Explain why these results cannot be used to determine how the current alone affects the force on the coil.
13 exam-style questions on AQA GCSE Physics 7.2 The motor effect, covering 7.2.1 Electromagnetism, 7.2.2 Fleming's left-hand rule (HT only), 7.2.3 Electric motors (HT only), and 7.2.4 Loudspeakers (HT only). Each one has a worked solution and a mark scheme showing where the marks go.