Question

In an A.C. generator, the speed at which the coil rotates is doubled. How would this effect (a) the frequency of the output voltage, (b) the maximum output voltage?

Answer 1

(a) In an a.c generator, if the speed at which the coil rotates is doubled, the frequency is also doubled.
(b) The maximum output voltage is also doubled. As voltage produced is proportional to the rate of change of the magnetic field. The induced voltage is related to the rate of change of magnetic flux linked with the coil. If the coil is rotating faster then the magnetic flux linked with the coil will change faster thus inducing a larger voltage.