Electrical Machines A 4 pole dynamo with wave wound armature has 51 slots contains 20 conductors in each slot. If induced emf 357 Volts and speed is 8500 rpm, flux per pole will be 2.7 mWb. 1.2 mWb. 1.4 mWb. 3.5 mWb. 2.7 mWb. 1.2 mWb. 1.4 mWb. 3.5 mWb. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Considering a galvanometer is connected to the rotor of a 3 - Φ, 4 pole, 50 Hz IM and is making 130 oscillations in a minute, then calculate the rotor speed? 1450. 1440. 1435. 1500. 1450. 1440. 1435. 1500. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A dc shunt generator, when driven without any excitation, showed an open circuit voltage of 12 V. When the field winding was excited, the voltage dropped to zero. It happened because there was no residual magnetism in the field circuit field resistance was higher than critical resistance there was a break in the armature circuit field winding was wrongly connected there was no residual magnetism in the field circuit field resistance was higher than critical resistance there was a break in the armature circuit field winding was wrongly connected ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the back emf in DC motor vanishes suddenly the motor will run at very high speed. burn. run at very low speed. start haunting. run at very high speed. burn. run at very low speed. start haunting. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following is/are not a self starting motor? 3-phase induction motor None of these both 1 and 2 1-phase induction motor 3-phase induction motor None of these both 1 and 2 1-phase induction motor ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A large series motor is never started without some mechanical load on it because otherwise it will produce sparking at brushes. open fuse or circuit breaker. draw too much current. develop excessive speed and damage itself. produce sparking at brushes. open fuse or circuit breaker. draw too much current. develop excessive speed and damage itself. ANSWER DOWNLOAD EXAMIANS APP