1. A universal motor can be operated on 220 V dc as well as 220V single phase ac. Which of the following will be same in the two cases?
  • Operating speed
  • Power output
  • Operating speed and power output
  • None of the above
  1. The motor used in ceiling fans is
  • Resistance split phase motor
  • Capacitor start motor
  • Capacitor start capacitor run motor
  • Slip ring motor
  1. A single phase motor is made self-starting by the addition of a/an
  • Running winding
  • Starting winding
  • Electric starter
  • Autotransformer
  1. Which of the following motors can work satisfactorily on both AC and DC?
  • Series motor
  • Shunt motor
  • Induction motor
  • Synchronous motor
  1. AC series motors are built with as few turns as possible to reduce
  • Flux
  • Reactance
  • Iron losses
  • Speed
  1. Universal motor is a _______ motor.
  • Series
  • Single phase induction
  • Synchronous
  • Shunt
  1. A universal motor is one which
  • Can run on any value of supply voltage
  • Has infinitely torque
  • Can operate on ac as well as dc voltage
  • Can work as single phase or three phase motor
  1. The single phase induction motor (IM) which does not have centrifugal switch is
  • Capacitor start single phase IM
  • Resistance split phase IM
  • Capacitor start capacitor run single phase IM
  • Permanent capacitor run single phase IM
  1. In capacitor start single phase induction motor, the current in the
  • Supply lines leads the voltage
  • Starting windings lags the voltage
  • Main winding leads the voltage
  • Starting winding leads the voltage
  1. At starting, the current through the starting winding (Is) of single phase induction motor
  • Lags ‘V’ by 900
  • Leads ‘V’ by 900
  • Is nearly in phase with ‘V’
  • Leads ‘V’ by 750
  1. In single phase induction motor, speed sensitive centrifugal switch in connected in _______ winding.
  • Parallel with main
  • Series with main
  • Parallel with starting
  • Series with starting
  1. Which of the following motor will give relatively high starting torque?
  • Shaded pole motor
  • Capacitor start motor
  • Capacitor run motor
  • Split phase motor
  1. A vacuum cleaner employs ______ motor.
  • Resistance split phase
  • Capacitor start
  • Shaded pole
  • Single phase series
  1. Which of the following single phase motors is available with speed as well as one revolution per minute?
  • Shaded pole
  • Reluctance
  • Hysteresis
  • Universal
  1. Which of the following motors can be run on as well as dc supply?
  • Reluctance motor
  • Universal motor
  • Repulsion motor
  • Synchronous motor
  1. The repulsion-start induction –run motor is used because of:
  • High starting torque
  • Good power factor
  • High efficiency
  • Minimum cost
  1. The least expensive fractional horse power motor is ______ motor:
  • Ac series
  • Shaded pole
  • Capacitor start
  • Split phase
  1. In which single-phase motor, the rotor has no teeth or winding?
  • Universal motor
  • Split phase motor
  • Reluctance motor
  • Hysteresis motor
  1. Low frequency operation of a.c. series motor in traction application:
  • Improves it commutation but starting current increases
  • Improves its commutation property but pf and efficiency reduces
  • Improves its commutation, pf and efficiency
  • Adversely affects commutation but pf and efficiency improves
  1. The purpose of starting winding is a single phase induction motor is to
  • Produce rotating flux in conjunction with main winding
  • Increase losses
  • Limit temperature rise of the machine
  • Reduce losses

 

  1. none of the above
  2. capacitor start capacitor run motor
  3. starting winding
  4. series motor
  5. reactance
  6. series
  7. can operate on ac as well as dc voltage
  8. permanent capacitor run single phase IM
  9. starting winding leads the voltage
  10. is nearly in phase with ‘V’
  11. series with starting
  12. capacitor start motor
  13. single phase series
  14. shaded pole
  15. universal motor
  16. high starting torque
  17. shaded pole
  18. hysteresis motor
  19. improves its commutation, pf and efficiency
  20. Produce rotating flux in conjunction with main winding