Industrial Drivers

1. _________ motor is a constant speed motor.

1. Synchronous motor
2. Schrage motor
3. Induction motor
4. Universal motor

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2. A pony motor is used for the starting which of the following motors?

1. Squirel cage induction motor
2. Schrage motor
3. Synchronous motor
4. None of the above

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3. A reluctance motor

1. is provided with slip rings
2. requires starting gear
3. has high cost
4. is compact

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4. A wound rotor induction motor is preferred, as compared to squirrel cage induction motor, when major consideration is

1. slop speed operation
2. high starting torque
3. low windage losses
4. all of the above

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5. Battery operated scooter for braking uses

1. plugging
2. mechanical braking
3. regenerative braking
4. rheostatic braking

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6. Belted slip ring induction motor is almost invariably used for

1. water pumps
2. jaw crushers
3. centrifugal blowers
4. none of the above

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7. Besides a constant speed a synchronous rotor possesses which of the following advantages?

1. Lower cost
2. Better efficiency
3. High power factor
4. All of the above

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8. By the use of which of the followingm D.C. can be obtained from AC.?

1. Silicon diodes
2. Mercury arc rectifier
3. Motor generator set
4. Any of the above

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9. Flame proof motors are used in

1. paper mills
2. steel mills
3. moist atmospheres
4. explosive atmospheres

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10. For a D.C. shunt motor which of the following is incorrect 7

1. Unsuitable for heavy duty starting
2. Torque varies as armature current
3. Torque-armature current is a straight line
4. Torque is zero for zero armature current

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