Synchronous Motors Mcqs

MCQ: In a synchronous motor, the breakdown torque is__________?

  1. directly proportional to the square of the applied voltage
  2. directly proportional to applied voltage
  3. inversely proportional to applied voltage
  4. none of the above

Releted Questions

Synchronous Motors Mcqs

MCQ: Synchronous motors are generally not self-starting because:

  1. the direction of rotation is not fixed
  2. the direction of instantaneous torque reverses after half cycle
  3. startes cannot be used on these machines
  4. starting winding is not provided on the machines

B

MCQ: In case one phase of a three-phase synchronous motor is short-circuited the motor will____________?

  1. not start
  2. run at 2/3 of synchronous speed
  3. run with excessive vibrations
  4. take less than the rated load

A

MCQ: A three-phase synchronous motor will have_____________?

  1. no slip-rings
  2. one slip-ring
  3. two slip-rings
  4. three slip-rings

C

MCQ: When V is the applied voltage, then the breakdown torque of a synchronous motor varies as_________?

  1. V
  2. V312
  3. V2
  4. 1/V

A

MCQ: The synchronous motor is not inherently self-starting because_______________?

  1. the force required to accelerate the rotor to the synchronous speed in an instant is absent
  2. the starting device to accelerate the rotor to near synchronous speed is absent
  3. a rotating magnetic field does not have enough poles
  4. the rotating magnetic field is produced by only 50 Hz frequency currents

A

Multiple Choice Questions and Answers