# Induction Motor MCQ Part 8

Electrical Engineering MCQ shares multiple choice questions on Induction Motor MCQ Part 8.

## Frequency of Induced EMF in Rotor of Induction Motor

A 4 pole, 50 Hz 3-phase induction motor has slip value of 4%. The frequency of induced emf in rotor is:

1. 1 Hz
2. 2 Hz
3. 12.5 Hz
4. 100 Hz

Solution: f’ = s*f

where f’ = rotor frequency

s = decimal slip

f = supply frequency

f’ = 0.04 * 50 = 2 Hz

## A four speed squirrel cage motor uses how many stator windings:

A four speed squirrel cage motor uses how many stator windings:

1. One
2. Two
3. Three
4. Four

Explanation: A four speed squirrel cage motor uses two stator windings. Each of these two provides two speeds.

## Induction Motor Speed Calculation Numerical

The full load slip of a 60 Hz, 3 phase, 6 pole induction motor is 4%. If rotor resistance is 0.02 per phase and standstill reactance is 0.2 per phase. What is the value of speed for which maximum torque will occur:

1. 400 RPM
2. 982 RPM
3. 1080 RPM
4. 1200 RPM