A. Lenz’s law
B. Ohm’s law
C. Faraday’s law of electromagnetic induction
D. none of the above
Related Mcqs:
- Two generators A and B have 6-poles each. Generator A has wave wound armature while generator B has lap wound armature. The ratio of the induced e.m.f. is generator A and B will be_______________?
A. 2 : 3
B. 3 : 1
C. 3 : 2
D. 1 : 3 - Which of the following components of a D.C, generator plays vital role for providing direct current of a D.C. generator ?
A. Dummy coils
B. Commutator
C. Eye bolt
D. Equilizer rings - The e.m.f. generated by a shunt wound D.C. generator isE. Now while pole flux remains constant, if the speed of the generator is doubled, the e.m.f. generated will be_______________?
A. E/2
B. 2E
C. slightly less than E
D. E - A separately excited generator as compared to a self-excited generator_____________?
A. is amenable to better voltage control
B. is more stable
C. has exciting current independent of load current
D. has all above features - The field coils of D.C. generator are usually made of_____________?
A. mica
B. copper
C. cast iron
D. carbon - In case of a 4-pole D.C. generator provided with a two layer lap winding with sixteen coils, the pole pitch will be__________________?
A. 4
B. 8
C. 16
D. 32 - An exciter for a turbo generator is a_____________?
A. separately excited generator
B. shunt generator
C. series generator
D. compound generator - The e.m.f. generated in a D.C. generator is directly proportional to____________?
A. flux/pole
B. speed of armature
C. number of poles
D. all of the above - In a D.C. generator:___________________?
A. external resistance = internal char-acteristic – armature reaction
B. internal characteristic = magnetisation characteristic – ohmic drop
C. external characteristic = magnetisation characteristic – ohmic drop – armature reaction
D. magnetisation characteristic = external characteristic - If residual magnetism is present in a D.C. generator, the induced e.m.f. at zero speed will be____________?
A. zero
B. small
C. the same as rated voltage
D. high
