Induction Motors Speed Control MCQ

Test your knowledge with important Induction Motors Speed Control MCQ and their applications. These MCQs are beneficial for competitive exams too. Explore 30+ more Induction Motors Speed Control MCQs on Bissoy. Bissoy App

• The value of slip at which maximum torque occurs ________
  ক

  R2÷X2

  খ

  4R2÷X2

  গ

  2R2÷X2

  ঘ

  R2÷3X2
• Calculate the total heat dissipated in a resistor of 44 Ω when 0 A current flows through it.
  ক

  0 W

  খ

  2 W

  গ

  1.5 W

  ঘ

  .3 W
• At low values of slip, the electromagnetic torque is directly proportional to ___________
  ক

  s

  খ

  s2

  গ

  s3

  ঘ

  s4
• If induction motor air gap power is 1.8 KW and gross developed power is .1 KW, then rotor ohmic loss will be _________ KW.
  ক

  1.7

  খ

  2.7

  গ

  3.7

  ঘ

  4.7
• The slope of the V-I curve is 9.1°. Calculate the value of resistance. Assume the relationship between voltage and current is a straight line.
  ক

  .16 Ω

  খ

  .26 Ω

  গ

  .25 Ω

  ঘ

  .44 Ω
• The slip recovery scheme is a part of the synchronous speed changing technique.
  ক

  True

  খ

  False
• The rotor injection method is a part of the slip changing technique.
  ক

  True

  খ

  False
• In the rotor voltage injection method, when an external voltage source is in opposite phase with the main voltage then speed will ___________
  ক

  Increase

  খ

  Decrease

  গ

  Remain unchanged

  ঘ

  First increases then decrease
• R.M.S value of the periodic square waveform of amplitude 72 V.
  ক

  72 V

  খ

  56 V

  গ

  12 V

  ঘ

  33 V
• Calculate the average value of the sinusoidal waveform x(t)=848sin(1.65πt+2π÷0.68).
  ক

  0

  খ

  78 V

  গ

  15 V

  ঘ

  85 V
• A 2-pole, 3-phase, ______ Hz induction motor is operating at a speed of 550 rpm. The frequency of the rotor current of the motor in Hz is 2.
  ক

  9.98

  খ

  9.71

  গ

  9.12

  ঘ

  9.37
• Calculate mark to space ratio if the system is on for 4.3 sec and off for 78.2 sec.
  ক

  .054

  খ

  .047

  গ

  .039

  ঘ

  .018
• Calculate the total heat dissipated in a rotor resistor of 14.23 Ω when .65 A current flows through it.
  ক

  6.45 W

  খ

  6.01 W

  গ

  6.78 W

  ঘ

  6.98 W
• Calculate the active power in a .89 H inductor.
  ক

  1.535 W

  খ

  0 W

  গ

  2.484 W

  ঘ

  1.598 W
• The power factor of a squirrel cage induction motor generally is ___________
  ক

  .6-.8

  খ

  .1-.2

  গ

  .2-.4

  ঘ

  .5-.7
• If induction motor rotor power is 157.5 KW and gross developed power is 79.9 KW, then rotor ohmic loss will be _________ KW.
  ক

  77.5

  খ

  77.6

  গ

  76.9

  ঘ

  77.1
• The slope of the V-I curve is 1.1°. Calculate the value of resistance. Assume the relationship between voltage and current is a straight line.
  ক

  .019 Ω

  খ

  .036 Ω

  গ

  .075 Ω

  ঘ

  .084 Ω
• Calculate the line voltage in star connection when phase voltage=45 V.
  ক

  77.9 V

  খ

  77.6 V

  গ

  77.2 V

  ঘ

  77.8 V
• If induction motor air gap power is 67 KW and mechanically developed power is 26 KW, then rotor ohmic loss will be _________ KW.
  ক

  41

  খ

  42

  গ

  43

  ঘ

  44
• The no-load circuit test on a 3-Φ induction motor is conducted at a rotor speed of _______
  ক

  Zero

  খ

  < Ns

  গ

  > Ns

  ঘ

  Ns
• R.M.S value of the sinusoidal waveform q(t)=2.11cos(87.25t+78π÷478.23).
  ক

  1.49 V

  খ

  1.56 V

  গ

  1.12 V

  ঘ

  1.78 V
• Calculate the amplitude of the sinusoidal waveform z(t)=.27sin(.369πt+.142π÷4.25).
  ক

  .287

  খ

  .270

  গ

  .216

  ঘ

  .287
• A 20-pole, 3-phase, 90 Hz induction motor is operating at a speed of _______ rpm. The frequency of the rotor current of the motor in Hz is 20.
  ক

  418.56

  খ

  420.12

  গ

  421.23

  ঘ

  422.45
• A 32-pole, 3-phase, 70 Hz induction motor is operating at a speed of 112 rpm. The frequency of the rotor current of the motor in Hz is __________
  ক

  40.2

  খ

  46.1

  গ

  40.1

  ঘ

  40.6