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9.1 A simplified diagram of an electric generator is shown below. When the coil is rotated with a constant speed, an emf is induced in the coil.
9.1.1 Is this an AC generator or a DC generator? (1)
9.1.2 Briefly explain how an emf is generated in the coil when the coil is rotated by referring to the
principle of electromagnetic induction. (2)
9.1.3 Draw a sketch graph of the output voltage versus time for this generator. Show ONE complete cycle. (2)
9.2 A 200 Ω resistor is connected to a DC voltage supply, as shown in diagram A. The energy dissipated in
the resistor in 10 s is 500 J.
The same resistor is now connected to an AC source (diagram B) and 500 J of energy is also dissipated in the resistor in 10 s.
9.2.1 Define the term rms voltage of an AC source. (2)
9.2.2 Calculate the maximum (peak) voltage of the AC source. (5)
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