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General
Easy
Question
A flat coil of wire is rotated at a frequency of 10 hertz in the magnetic field produced by three pairs of magnets as shown. The axis of rotation of the coil lies in the plane of the coil and is perpendicular to the field lines. What is the frequency of the alternating voltage in the coil?
- 10 Hz
- 30 Hz
- 60 Hz
- 10/3 Hz
The correct answer is: 30 Hz
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