Question

Voltmeter gives 120 oscillations per minute when connected to the rotor of an induction motor. The supply frequency is 50 hz. The slip of the motor i

Answer 1

Voltmeter is measuring 120 oscillations per minute i.e. frequency is 120/60 2HZ. 2 Hz is a rotor frequency. Now, Always in case of Induction motors, Rotor runs at "slip frequency" which is noting but "slip times supply frequency". Here slip frequency is 2 Hz and supply frequency given is 50 Hz i.e. Slip x (Supply frequency) 2Hz. Slip x (50) 2 Hz So, Slip 2/50 0.04

Answer 2

Voltmeter is measuring 120 oscillations per minute i.e. frequency is 120/60 = 2HZ.

2 Hz is a rotor frequency.

Now, Always in case of Induction motors, Rotor runs at “slip frequency” which is noting but “slip times supply frequency”.

Here slip frequency is 2 Hz and supply frequency given is 50 Hz.

i.e. Slip x (Supply frequency) = 2Hz.

Slip x (50) = 2 Hz

So, Slip = 2/50 = 0.04