Objective Questions on Torque Equation of Three Phase Induction Motor

  1. The torque developed by a 3-phase induction motor is approximately proportional to

    Under construction.

  2. The frequency of rotor currents at standstill is equal to

    Under construction.

  3. Insertion of resistance in the rotor circuit of an induction motor to develop a given torque causes ______________ in the rotor current.

    Under construction.

  4. The torque developed in an induction motor is nearly proportional to

    Under construction.

  5. The starting torque of a 3-phase induction motor varies as

    Under construction.

  6. For a constant torque load, the supply voltage of squirrel cage induction motor is reduced by a factor of 0.707, its rotor electric current is modified by a factor

    Under construction.

  7. In a 3-phase induction motor, the starting torque will be maximum when

    Under construction.

  8. The starting torque of a squirrel cage induction motor is

    Under construction.

  9. For achieving high starting torque and high operation efficiency an induction motor should have ________________ rotor circuit resistance at starting and ________________ circuit resistance under operating condition.

    Under construction.

  10. In a 3-phase induction motor, if stator impedance is neglected, then slip at maximum torque equal to

    Under construction.

  11. Breakdown torque of a 3-phase induction motor of negligible stator impedance is

    Under construction.

  12. Beyond the point of maximum torque any further increase in load will cause

    Under construction.

  13. In an induction motor, maximum torque varies as

    Under construction.

  14. Pull out torque in an induction motor occurs when power factor becomes

    Under construction.

  15. On decreasing the applied rated voltage/phase by one half, the starting torque of an induction motor becomes times of starting torque with full voltage

    Under construction.

  16. For 4 % drop in supply voltage, the torque of an induction motor increase by

    Under construction.

  17. In an induction motor, the torque in Nm is given as

    Under construction.

  18. If a motor shows symptoms of loss of torque with excessive vibrations, it can be concluded that

    Under construction.

  19. If the slip of the rotor of an induction motor is halved, the value of rotor reactance

    Under construction.

  20. The condition for maximum torque of the rotor of an induction motor is

    Under construction.