An engineer investigates how the number of turns and the speed of a coil affect the peak induced potential difference. A magnet is fixed beside the path of the coil, and the coil is moved past the magnet. The coil is connected to a data logger. For each reading, the same magnet, path and coil area are used, and only the stated variable is changed.
The results are shown in the table.
| Number of turns on coil | Speed of coil / cm s−1\text{cm s}^{-1}cm s−1 | Peak induced potential difference / mV\text{mV}mV |
|---|---|---|
| 200 | 10 | 18 |
| 400 | 10 | 36 |
| 200 | 20 | 36 |
Describe what the results show about the effects of the number of turns and the speed of the coil on the peak induced potential difference.
Use data from the table in your answer.
The engineer moves a 600-turn coil at 30 cm s-1 past the same magnet.
Predict the peak induced potential difference.
The engineer stops the coil beside the magnet.
Predict the potential difference across the stationary coil. Give a reason for your answer.
The external circuit connected to the coil is replaced by one with a larger resistance. The coil is moved past the magnet in the same way.
Predict how the peak induced potential difference and the induced current will change.
Give a reason for 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.