| 1. | A shearing machine has cyclic load consisting of intermittent light and henry loads. Which of the following D.C. motor will be suitable for this purpose ? | |
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Series motor
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Shunt motor
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Cumulative compound motor
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Differential compound motor
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Report Question| 2. | If a D.C. motor is connected across the A.C. supply it will ? | |
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run at normal speed
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not run
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run at lower speed
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burn due to heat produced in the field winding by eddy currents
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| 3. | To get the speed of D.C motor below the normal without wastage of electrical energy ...... is used ? | |
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Ward Leonard control
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rheostatic control
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any of the above method
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none of the above method
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| 4. | According to Fleming's left-hand-rule, when the forefinger points in the direction of the field or flux, middle finger wilt point in the direction of ? | |
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current in the conductor
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movement of conductor
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resultant force on conductor
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none of the above
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| 5. | Which D.C. motor will preferred, for machine tools ? | |
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Series motor
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Shunt motor
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Cumulative compound motor
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Differential compound motor
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| 6. | For starting a D.C. motor a starter is. required because ? | |
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it limits the speed of the motor
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it limits the starting current to a safe value
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it starts the rotor
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none of the above
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| 7. | A direct on line starter is used for starting motors ? | |
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up to 5 H.P.
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up to 10 H.P.
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up to 15 H.P.
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up to 20 H.P.
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| 8. | By looking at which part of the motor, it can be easily confirmed that a particular motor is D.C. motor ? | |
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Frame
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Shaft
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Commutator
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Stator
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| 9. | If the terminals of armature of D.C. motor are interchanged, this action will offer following kind of braking ? | |
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regenerative
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plugging
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dynamic braking
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none of the above
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| 10. | For which types of D.C. motor, dynamic braking is generally used ? | |
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Shunt motors
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Series motors
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Compound motors
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All of the above
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