SOLUTION

Mechanical Degree: Mechanical degree or angle is the angle at which the rotor of a machine is displaced mechanically.

Electrical Degree: The degree or the cycle of emf induced in a single conductor in a synchronous machine. In one electrical cycle, the electrical angle varies from 0-360 degree

• Consider a 4 pole machine there are 2 North and 2 South poles. So the rotor had to rotate 180 degrees mechanically to reach from one North pole to another North pole.
• That is to generate a complete cycle(360 degrees) electrically it has to rotate half cycle(180 degrees)mechanically.
• So the relation between electrical and mechanical angle is dependent on the no of poles in the machine.

Electrical Degree = (No of poles/2) × Mechanical Degree

8 = (4/2) × Mechanical Degree

Mechanical Degree = 4°