Electrical Machines Variation in speed by ward-Leonard control of DC motors occurs due to variation in Armature current. Armature voltage. Supply voltage. Field excitaion. Armature current. Armature voltage. Supply voltage. Field excitaion. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Eg (generated emf) and Eb (back emf) both are same. different. changes. none of above. same. different. changes. none of above. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which type of bearing is provided in small induction motors to support the rotor shaft? None of these Bush bearings. Ball bearings. Cast iron bearings. None of these Bush bearings. Ball bearings. Cast iron bearings. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Field weakening control method is used for the _________ ? above rated speed None of these below rated speed both A and B above rated speed None of these below rated speed both A and B ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC series motor is running with a divertor connected across its field winding. If the divertor resistance is reduced then the speed of the motor will increase. decrease. remain unaltered. become execessively high. increase. decrease. remain unaltered. become execessively high. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC shunt generator builds up to a voltage of 220 V at no load while running at its rated speed. If the speed of the generator is raised by 25% kepping the circuit conditions unaltered, then the Voltage to which the machine would build up will not change and remain at 220 V increase to a value greater than 1.25 times 220 V increase to value lying between 220 V and 1.25 times 220 V increase to 1.25 times 220 V not change and remain at 220 V increase to a value greater than 1.25 times 220 V increase to value lying between 220 V and 1.25 times 220 V increase to 1.25 times 220 V ANSWER DOWNLOAD EXAMIANS APP
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