| 1. | The generated e.m.f and the current are in the opposite direction in case of ? | |
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d.c. generators
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d.c. motors
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both (a) and (b)
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none of the above
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Report Question| 2. | While starting a differential compound motor, it is best to short the series field in order to avoid ? | |
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excessive starting period
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motor starting in wrong direction
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tripping of the circuit breaker
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large in rush of current
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| 3. | Which D.C. motor has got maximum self relieving property ? | |
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Series motor
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Shunt motor
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Cumulatively compounded motor
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Differentially compounded motor
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| 4. | If a D.C. shunt motor is working at full load and if shunt field circuit suddenly opens ? | |
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this will make armature to take heavy current, possibly burning it
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this will result in excessive speed, possibly destroying armature due to excessive centrifugal stresses
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nothing will happen to motor
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motor will come to stop
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| 5. | The armature voltage control of D.C. motor provides ? | |
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constant torque drive
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constant voltage drive
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constant current drive
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none of the above
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| 6. | A motor for punching machine is usually subjected to ? | |
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no load
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continuous part load
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continuous full load
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intermittent Load
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| 7. | When the armature of a D.C. motor rotates, e.m.f. induced is ? | |
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self-induced e.m.f.
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mutually induced e.m.f.
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back e.m.f.
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none of the above
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| 8. | If the speed of a D.C. shunt motor is increased the back e.m.f. of the motor will ? | |
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decrease
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increase
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remain same
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become zero
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| 9. | Sparking is discouraged in a D.C. motor because ? | |
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it increases the input power consumption
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commutator gets damaged
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both (a) and (b)
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none of the above
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| 10. | Which D.C. motor bas got maximum self loading property ? | |
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Series motor
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Shunt motor
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Cumulatively compounded motor
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Differentially compounded motor
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