Electrical Machines In a 3 - Φ IM with line frequency f1 and winding factor kw1 and kw2 for stator and rotor respectively the ratio of per phase stator winding emf E1 to per phase rotor winding emf E2 at standstill is given by E1 / E2 = N1kw1 / N2kw2. E1 / E2 = f1kw1 / f2kw2. E1 / E2 = N1 / N2. E1 / E2 = 1. E1 / E2 = N1kw1 / N2kw2. E1 / E2 = f1kw1 / f2kw2. E1 / E2 = N1 / N2. E1 / E2 = 1. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the back emf in DC motor vanishes suddenly the motor will run at very low speed. burn. start haunting. run at very high speed. run at very low speed. burn. start haunting. run at very high speed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The mmf produced by rotor currents of a 3 - Φ induction motor rotates at slip speed with respect to stator mmf. rotates at synchronous speed with respect to rotor. is at standstill with respect to stator mmf. rotates at the speed of rotor in the air gap. rotates at slip speed with respect to stator mmf. rotates at synchronous speed with respect to rotor. is at standstill with respect to stator mmf. rotates at the speed of rotor in the air gap. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The use of higher flux density in the transformer design None of these reduces the weigh per KVA has no relation with the weight of transformer increases the weigh per KVA None of these reduces the weigh per KVA has no relation with the weight of transformer increases the weigh per KVA ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 4 pole wave wound dc motor having flux per pole of 9.56 X 10-3 Wb contains 460 armature conductors. Calculate the back emf produced when it is running at a speed of 1500 rpm. 230 volt. 240 volt. 220 volt. 440 volt. 230 volt. 240 volt. 220 volt. 440 volt. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In speed control of DC shunt motor by varying field flux, what may be the value of field regulator? 10 ohm 2 ohm. 0.2 ohm 100 ohm 10 ohm 2 ohm. 0.2 ohm 100 ohm ANSWER DOWNLOAD EXAMIANS APP
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