| 1. | The speed of a D.C. shunt motor can be increased by ? | |
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increasing the resistance in armature circuit
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increasing the resistance in field circuit
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reducing the resistance in the field circuit
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reducing the resistance in the armature circuit
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Report Question| 2. | ln the D.C. motor the iron losses occur in ? | |
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the field
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the armature
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the brushes
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the commutator
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| 3. | The main disadvantage of the Ward Leonard control method is ? | |
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high initial cost
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high maintenance cost
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low efficiency at light loads
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all of the above
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| 4. | The retardation test is applicable to shunt motors and generators and is used to find ? | |
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the copper losses
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the stray losses
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the friction losses
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the eddy current losses
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| 5. | A series motor is best suited for driving ? | |
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machine tools
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cranes and hoists
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shear and punches
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none of the above
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| 6. | When the electric train is moving down a hill the D.C. motor act as ? | |
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D.C series generator
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D.C. shunt generator
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D.C. shunt motor
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D.C. series motor
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| 7. | Which of the following motors, on removal of load, will run at the highest speed ? | |
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Shunt motor
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Series motor
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Differential compound
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Cumulative compound
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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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increase
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decrease
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remain same
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become zero
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| 9. | In a DC generator, the iron losses mainly take place in ? | |
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yoke
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commutator
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armature conductors
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armature rotor
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| 10. | Which one of the following is not necessarily the advantage of D.C. motors over AC. Motors ? | |
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Low cost
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Wide speed range
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Stability
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High starting torque
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