Electrical Machines Commutators in DC machines have a role of which converts Both AC to DC and DC to AC. AC to DC. high voltage DC to low voltage DC. none of these. Both AC to DC and DC to AC. AC to DC. high voltage DC to low voltage DC. none of these. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An IM cannot run at synchronous speed because induction motor will become synchronous motor. air friction will prevent it. none of above. rotor torque will not be produced. induction motor will become synchronous motor. air friction will prevent it. none of above. rotor torque will not be produced. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Brushes are always placed on--------------- , in order to achieve sparkles commutation? GNA None of these MNA either GNA or MNA GNA None of these MNA either GNA or MNA ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The squirrel cage induction motors are provided with blades in order to none of these. balance the rotor dynamically. eliminate noise. facilitate cooling of rotor. none of these. balance the rotor dynamically. eliminate noise. facilitate cooling of rotor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The direction of generated emf in the armature coil of a DC machine is 1. the same as that of the current in a generator 2. the same as that of the current in a motor 3. opposite to that of the current in a generator 4. opposite to that of the current in a motor From these, the correct answer is 2, 4 1, 4 2, 3 1, 3 2, 4 1, 4 2, 3 1, 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines To eliminate the 5th harmonic in the induced voltages their respective pitch factor angle should be 30° 72° 36° 18° 30° 72° 36° 18° ANSWER DOWNLOAD EXAMIANS APP