Electrical Machines The squirrel cage induction motors are provided with blades in order to eliminate noise. facilitate cooling of rotor. balance the rotor dynamically. none of these. eliminate noise. facilitate cooling of rotor. balance the rotor dynamically. none of these. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A self-excited shunt generator fails to build up, because 1. the field circuit is open 2. The armature circuit is open 3. the residual magnetism is absent 4. The direction of rotation is wrong From these, the correct answer is 1, 2 and 3 1, 3 3 only 1, 2, 3 and 4 1, 2 and 3 1, 3 3 only 1, 2, 3 and 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines With the increase in speed of a DC motor both back emf as well as line current fall. both back emf as well as line current increase. back emf increases but line current falls. back emf falls and line current increases. both back emf as well as line current fall. both back emf as well as line current increase. back emf increases but line current falls. back emf falls and line current increases. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Armature coil is short circuited by brushes when it lies along neutral axis. in any of above positions. in none of above positions. along field axis. along neutral axis. in any of above positions. in none of above positions. along field axis. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The functions of inter poles are None of these nullify reactance voltage and improve the commutation. reduce cross magnetization effect and improve commutation both 1 and 2 None of these nullify reactance voltage and improve the commutation. reduce cross magnetization effect and improve commutation both 1 and 2 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If in a sub – station there is one 132 / 33 kV transformer whose secondary is connected with primary of one 33 / 11 kV transformer, the total transformation ratio of the sub – station will be, 7. 12. 3. 4. 7. 12. 3. 4. ANSWER DOWNLOAD EXAMIANS APP
EXAMIANS