A 2-pole, 3-phase, ______ Hz induction motor is operating at a speed of 550 rpm. The frequency of the rotor current of the motor in Hz is 2.
(a) 9.98
(b) 9.71
(c) 9.12
(d) 9.37
The question was asked in an international level competition.
This interesting question is from Induction Motors Speed Control in portion Speed Control of Direct Current Motors & Induction Motors of Electric Drives