Electrical Machines When maximum starting torque is obtained, rotor power is ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 4-pole dc generator runs at 1500 rpm. The frequencyof current in the armature winding is 100 Hz 0 Hz 25 Hz 50 Hz 100 Hz 0 Hz 25 Hz 50 Hz 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 2, 4, 5, 6 3, 4, 5 2, 3, 6 1, 2, 5 2, 4, 5, 6 3, 4, 5 2, 3, 6 1, 2, 5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Compensating windings are used in DC generators None of these to neutralize the cross magnetizing effect of the armature reaction. to provide path for the circulation of cooling air. mainly to reduce the eddy currents by providing local short circuit. None of these to neutralize the cross magnetizing effect of the armature reaction. to provide path for the circulation of cooling air. mainly to reduce the eddy currents by providing local short circuit. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of following DC motors will have percentage increase of input current for the same percentage increase in torque? Differntical compound. Shunt. Series. Cummulative compound. Differntical compound. Shunt. Series. Cummulative compound. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a 3 - φ induction motor running at full load which of these parameters is stationary with respect to the stator mmf wave? Stator winding. Both rotor and stator winding. Rotor mmf wave. Rotor winding. Stator winding. Both rotor and stator winding. Rotor mmf wave. Rotor winding. ANSWER DOWNLOAD EXAMIANS APP
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