A three-phase induction motor has 8 poles, and it runs on a supply frequency of 60 Hz. Find the speed of the rotating magnetic field.

A 4-pole, 50 Hz induction motor operates at 7% slip. The frequency of the EMF induced in the rotor will be:

In a brake test on a DC motor, the motor takes 20 A from 200 V supply mains. The brake pulley of radius 10 cm has an effective load of 20 kg and the speed is 10 rps. Taking g = 9.81 m/s2, the value of Brake Horse Power (BHP in metric units, where 1 metric HP = 735.5 W) is approximately: