Electrical Machines If s is the slip and f is the supply frequency of an induction motor, the frequency of rotor current is given by f / s. sf / 2. sf. s2. f / s. sf / 2. sf. s2. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A smaller air gap in a induction motor helps to reduce the magnetizing current. reduce the chance of cogging. reduce the chance of crawling. increase the starting torque. reduce the magnetizing current. reduce the chance of cogging. reduce the chance of crawling. increase the starting torque. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines No load test of 3-phase induction motor gives which of the following? constant loss None of these both A and B variable loss constant loss None of these both A and B variable loss ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Ideal value of voltage regulation of a device is? ∞ 0 a positive finite value a finite negative value ∞ 0 a positive finite value a finite negative value ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the back emf in DC motor vanishes suddenly the motor will burn. run at very low speed. start haunting. run at very high speed. burn. run at very low speed. start haunting. run at very high speed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If starting current of a 3 - Φ induction motor is 5 times the rated current, while rated slip is 4 %, then ratio of starting torque to full load torque is 0.8. 0.6. 0.4. 1. 0.8. 0.6. 0.4. 1. ANSWER DOWNLOAD EXAMIANS APP