Electrical Machines In a DC generator, if P be the number of poles and N be the rpm of the rotor, then frequency of magnetic reversals will be PN/120. PN/60. PN/2. PN/3000. PN/120. PN/60. PN/2. PN/3000. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the back emf in DC motor vanishes suddenly the motor will start haunting. run at very low speed. burn. run at very high speed. start haunting. run at very low speed. burn. run at very high speed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In case of a dc motor the ratio Eb / E is indicative of ratio of starting to running current. efficiency. ratio of starting to running torque. ratio of input to output voltage. ratio of starting to running current. efficiency. ratio of starting to running torque. ratio of input to output voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which motor cannot be started on no load? both B and C cumulative compound motors shunt motors series motors both B and C cumulative compound motors shunt motors series motors ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3 - Φ induction motor draws an current of 50 A from mains when starts by direct switching. If an auto transformer with 60 % tapping is used for starting the current drawn from the mains will be 80. 50. 36. 18. 80. 50. 36. 18. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of these types of motor is self starting? Poly-phase induction motor. Single phase induction motor. Poly-phase synchronous machine. None of these. Poly-phase induction motor. Single phase induction motor. Poly-phase synchronous machine. None of these. ANSWER DOWNLOAD EXAMIANS APP