A hand-cranked alternator has a rotating coil in a magnetic field. Students measure its peak potential difference at different rotation rates and with different coils.
| Number of turns | Rotation rate in rotations per minute | Peak potential difference in V |
|---|---|---|
| 100 | 60 | 0.40 |
| 100 | 120 | 0.80 |
| 200 | 60 | 0.80 |
The alternator is then fitted with a 200-turn coil and cranked at 90 rotations per minute.
Calculate the frequency of the alternator's output at 90 rotations per minute.
Calculate the peak potential difference produced in this final setup. Explain how the results in the table support your answer.
92 exam-style questions on Edexcel GCSE Physics 13.1 Inducing a current, covering 13.1.1 Producing an electric current by induction, 13.1.2 Factors affecting the induced potential difference, 13.1.3 Alternators and dynamos, and 13.1.4 Microphones and loudspeakers. Each one has a worked solution and a mark scheme showing where the marks go.