Electrical Machines In which of the following DC Motor the ratio of starting torque to full load torque is minimum? Cumulative compound motor. Shunt motor. Series motor. Differential compound motor. Cumulative compound motor. Shunt motor. Series motor. Differential compound motor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the field of a dc shunt motor gets opened while the motor is running, then the motor will become slow. armature current will drop motor will attain dangerously high speed armature will oscillate about original speed as the mean speed motor will become slow. armature current will drop motor will attain dangerously high speed armature will oscillate about original speed as the mean speed ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When applied rated voltage per phase is reduce to one half, the starting torque of three phase squirrel cage induction motor becomes 4 time the initial value 1/2 of the initial value twice the initial value 1/4 of the intial value 4 time the initial value 1/2 of the initial value twice the initial value 1/4 of the intial value ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In Ward-Leonard system, the lower limit of the speed imposed by None of above. Field resistance. Armature resistance. Residual magnetism of the generator. None of above. Field resistance. Armature resistance. Residual magnetism of the generator. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In an induction motor, the no-load slip is generally equal to 4 %. 1.5 %. zero. less than 1 %. 4 %. 1.5 %. zero. less than 1 %. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Semi closed slots or totally closed slots are used in induction motors, essentially to decrease starting torque increase pull out torque improve starting torque reduce magnetising current and improve power factor decrease starting torque increase pull out torque improve starting torque reduce magnetising current and improve power factor ANSWER DOWNLOAD EXAMIANS APP