Electrical Machines The speed of stator rotating magnetic field (RMF) with respect to rotor is S.Ns Nr Ns Zero S.Ns Nr Ns Zero ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The counter (or back) emf in a dc machine is 1. the same as generated emf in a dc motor 2. proportional to field flux and armature speed 3. not the same as generated emf in a dc motor 4.inversely proportional to field flux 5. proportional to number of armature conductors 6. constant from no load to full load From these, the correct answer is 3, 4, 5 2, 4, 5, 6 1, 2, 5 2, 3, 6 3, 4, 5 2, 4, 5, 6 1, 2, 5 2, 3, 6 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines To eliminate 5th harmonic in the induced voltage phase breadth should be 30° 72° 18° 36° 30° 72° 18° 36° ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In synchronous motor, the damper winding is generally used to provide starting torque only. reduce the eddy currents. prevent hunting and provide the starting torque. reduce noise level only. provide starting torque only. reduce the eddy currents. prevent hunting and provide the starting torque. reduce noise level only. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Neglecting all losses, the developed torque (T) of DC separately excited motor, operating under constant terminal voltage is reduced to its output power (P) as T2 ∝ P3. T ∝ √P. T is independent of P. T ∝ P. T2 ∝ P3. T ∝ √P. T is independent of P. T ∝ P. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Pole changing methods are suitable only for ___________ type induction motor. none of these. wound. linear. cage. none of these. wound. linear. cage. ANSWER DOWNLOAD EXAMIANS APP
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