| 1. | Which of the following load normally, needs starting torque more than. The rated torque ? | |
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Blowers
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Conveyors
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Air compressors
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Centrifugal pumps
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Report Question| 2. | Usually wide and sensitive speed control is desired in case of ? | |
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centrifugal pumps
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elevators
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steel rolling mills
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colliery winders
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| 3. | Small D.C. motors up to 5 H.P. usually have ? | |
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2 poles
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4 poles
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6 poles
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8 poles
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| 4. | For which of the following applications a D.C. motor is preferred over an A.C. motor ? | |
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Low speed operation
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High speed operation
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Variable speed operation
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Fixed speed operation
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| 5. | Following motor ls used where high starting torque and wide speed range control is required ? | |
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Single phase capacitor start
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Induction motor
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Synchronous motor
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D.C. motor
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| 6. | Compensating winding in a D.C. machine is placed ? | |
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on yoke in the pole faces
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on yoke in the interpolar gap
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on armature
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none of the above
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| 7. | D.C. motor is to a drive a load which is almost nil for certain part of the load cycle and peak value for short duration. We will select this ? | |
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series motor
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shunt motor
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compound motor
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any of the above
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| 8. | In a D.C. motor if the back e.m.f. is absent ? | |
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motor will burn
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motor will not run at all
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motor will run at very slow speed
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motor will run at very high speed
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| 9. | Which of the following methods is most economical for finding the no-load losses of a large D.C shunt motor ? | |
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Retardation test
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Swinburne's test
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Hopkinson's test
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none of the above
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| 10. | In an overloaded motor main danger arises due to ? | |
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winding getting overheated
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busbars getting heated
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starter getting damaged
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bearings getting overheated
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