Electrical Machines What is the necessity of copper brushes in a dc motors? To increase the flux cutting by the rotor. To convert alternating supply current to direct current. To absorb the mechanical shocks produced during running condition. None of these. To increase the flux cutting by the rotor. To convert alternating supply current to direct current. To absorb the mechanical shocks produced during running condition. None of these. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The interpoles in dc machines have a tapering shape in order to reduce the saturation in the interpole increase the acceleration of commutation reduce the overall weight economise on the material required for interpoles and their windings reduce the saturation in the interpole increase the acceleration of commutation reduce the overall weight economise on the material required for interpoles and their windings ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC series motor is accidentally connected to single phase ac supply voltage. The torque produced will be oscillating None of these pulsating and unidirectional steady and unidirectional oscillating None of these pulsating and unidirectional steady and unidirectional ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The shaft torque of a dc motor is less than the electromagnetic torque because of eddy current losses. ohmic losses. mechanical losses. hysteresis losses. eddy current losses. ohmic losses. mechanical losses. hysteresis losses. 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? Rotor winding. Rotor mmf wave. Both rotor and stator winding. Stator winding. Rotor winding. Rotor mmf wave. Both rotor and stator winding. Stator winding. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC series motor has which of the following characteristics? Has its field winding consinting of thick wire and less no of turns. Has a poor torque. Has a almost constant speed. Can be started easily without load. Has its field winding consinting of thick wire and less no of turns. Has a poor torque. Has a almost constant speed. Can be started easily without load. ANSWER DOWNLOAD EXAMIANS APP
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