What happens to the voltage as the generator makes one complete rotation (360 degrees)?

When a generator makes one complete rotation (360 degrees), the voltage generated varies in a sinusoidal manner, which is typical for alternating current (AC) generators. At the start of the rotation, the voltage begins at a certain level, usually zero volts, as the rotor begins to move through the magnetic field. As the generator rotates, the angle between the rotor and the magnetic field changes, causing the induced voltage to rise to a maximum positive value, then decrease back to zero, continue to a maximum negative value, and finally return to its original starting value.

This cyclical process of the voltage changing in both positive and negative directions corresponds to the continuous motion of the generator’s rotor. Therefore, after one complete rotation, the electrical output voltage does indeed return to its starting point, completing a full cycle. This behavior is foundational in understanding how AC generators operate, producing alternating voltage.

The uniformity of the voltage pattern during each complete rotation is essential for establishing the frequency of the generated power. Recognizing this cycle is crucial for analyzing and designing electrical systems using AC generators.