Final answer:
The frequency of an AC signal from an AC alternator is determined by the rpm of the rotor and the number of poles.
Step-by-step explanation:
The frequency of an AC signal produced from an AC alternator is determined by the rpm of the rotor and the number of poles.
When an alternator is rotated at a constant speed, the number of times the magnetic field lines are cut by the windings of the rotor determines the frequency of the AC signal. This is directly proportional to the rotor's rpm. Additionally, the number of poles in the alternator determines the number of cycles produced per revolution, impacting the frequency as well.
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