Single Phase Induction Motors

41. In capacitor start single-phase motors

1. current in the starting winding leads the voltage
2. current in the starting winding lags the voltage
3. current in the starting winding is in phase with voltage in running winding
4. none of the above

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42. In case of a reluctance motor, when the load is increased so that it cannot maintain synchronous speed the motor will

1. become unstable
2. draw excessive armature current and may burn out
3. fall out of synchronism and come to stand still
4. run as induction motor

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43. In case of a shaded pole motor the direction of rotation of the motor is

1. from main pole to shaded pole
2. from shaded pole to main pole
3. either of the above depending on voltage
4. either of the above depending on power factor

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44. In case of high speed universal motor which of the following needs more attention?

1. End play
2. Air gap
3. Insulation in rotor
4. Balancing of rotor

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45. In repulsion motor direction of rotation of motor

1. is opposite to that of brush shift
2. is the same as that of brush shift
3. is independent of brush shift
4. None of these

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46. In repulsion motor, maximum torque is developed when

1. brush axis is at 45° electrical to the field axis
2. brush axis coincides with the field axis
3. brush axis is at 90° electrical to the field axis
4. none of the above

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47. In repulsion motor, zero torque is developed when

1. brush axis is 45° electrical to field axis
2. brush axis coincides with the field axis
3. brush axis is 90° electrical to field axis
4. both (b) and (c)

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48. In split phase motor main winding is of

1. thin wire placed at the top of the slots
2. thin wire placed at the bottom of the slots
3. thick wire placed at the bottom of the slots
4. thick wire placed at the top of the” slots

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49. In split-phase motor auxiliary winding is of

1. thick wire placed at the bottom of the slots
2. thick wire placed at the top of the slots
3. thin wire placed at the top of the slots
4. thin wire placed at the bottom of the slots

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50. In which single-phase motor, the rotor has no teeth or winding?

1. Split phase motor
2. Reluctance motor
3. Hysteresis motor
4. Universal motor

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