What happens to the output voltage of an AC generator as the speed of rotation increases?

When the speed of rotation of an AC generator increases, the output voltage also increases. This relationship is based on Faraday's law of electromagnetic induction, which states that the induced voltage in a coil is proportional to the rate of change of magnetic flux. In the context of an AC generator, as the rotor spins faster, it cuts through magnetic lines of force more rapidly, resulting in a higher rate of change of magnetic flux.

As a result, the induced electromotive force (EMF) increases with the speed of rotation, leading to a greater output voltage. This principle is essential in understanding how AC generators work and how their performance can be modified by changing the rotation speed. The other options do not accurately reflect the relationship between speed and output voltage in an AC generator, reinforcing the understanding that increasing speed will indeed lead to an increased voltage output.