Electrical Machines Pole changing methods are suitable only for ___________ type induction motor. cage. linear. none of these. wound. cage. linear. none of these. wound. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The rotor of a three phase induction motor has an impedance of 0.4 + j4 ohm per phase at standstill the maximum torque occurs at a slip of _____________. 10 %. 15 %. 25 %. 50 %. 10 %. 15 %. 25 %. 50 %. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Air core transformer as compared to iron core transformer, has less magnetic core loss. no magnetic core loss. more copper loss. more magnetic core loss. less magnetic core loss. no magnetic core loss. more copper loss. more magnetic core loss. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 220 ,V 15 , kW 100 rpm shunt motor with armature resistance of 0.25 , W has a rated line current of 68 A and a rated field current of 2.2 A. The change in field flux required to obtain a speed of 1600 rpm while drawing a line current of 52.8 A and a field current of 1.8 A is 36.36% decrease 36.36% increase 36.36% increase 18.18% increase 36.36% decrease 36.36% increase 36.36% increase 18.18% increase ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The mmf produced by rotor currents of a 3 - Φ induction motor rotates at synchronous speed with respect to rotor. rotates at slip speed with respect to stator mmf. rotates at the speed of rotor in the air gap. is at standstill with respect to stator mmf. rotates at synchronous speed with respect to rotor. rotates at slip speed with respect to stator mmf. rotates at the speed of rotor in the air gap. is at standstill with respect to stator mmf. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Autotransformer makes effective saving on copper and copper losses, when its transformation ratio is equal to very low approx to one. greater than one. less than one. very low approx to one. greater than one. less than one. ANSWER DOWNLOAD EXAMIANS APP