Single phase induction motors

[amp_mcq option1=”Split phase motor” option2=”Universal motor” option3=”Hysteresis motor” option4=”Shaded pole motor” correct=”option4″]

Detailed SolutionWhich motor is normally free from mechanical and magnetic vibrations ?

[amp_mcq option1=”Split motor” option2=”Shaded-pole motor” option3=”Reluctance motor” option4=”None of these” correct=”option1″]

Detailed SolutionWhich of the following motors is inherently self starting ?

[amp_mcq option1=”End play” option2=”Air gap” option3=”Insulation in rotor” option4=”Balancing of rotor” correct=”option2″]

Detailed SolutionIn case of high speed universal motor which of the following needs more attention ?

[amp_mcq option1=”high inductance of field and armature circuits” option2=”induced current in rotor due to variations of flux” option3=”series motor is connected to A.C. supply, the power factor will be low because of A. high inductance of field and armature circuits B. induced current in rotor due to variations of flux C. fine copper wire winding” option4=”none of the above” correct=”option1″]

Detailed SolutionWhen a D.C. series motor is connected to

[amp_mcq option1=”D.C. only” option2=”D.” option3=”only B.” option4=”none of the above” correct=”option3″]

Detailed SolutionA universal motor can run on

[amp_mcq option1=”brush axis is at 45° electrical to the field axis” option2=”brush axis coincides with the field axis” option3=”brush axis is at 90° electrical to the field axis” option4=”none of the above” correct=”option1″]

Detailed SolutionIn repulsion motor, maximum torque is developed when

[amp_mcq option1=”200 to 250 W” option2=”250 to 500 W” option3=”50 to 150 W” option4=”10 to 20 W” correct=”option3″]

Detailed SolutionThe wattage rating for a ceiling fan motor will be in the range

[amp_mcq option1=”D.C. shunt motor” option2=”Schrage motor” option3=”shunt motor B. Schrage motor C. Repulsion start and induction run motor” option4=”Universal motor” correct=”option4″]

Detailed SolutionWhich of the following motor will give the highest starting torque ?

[amp_mcq option1=”It is similar to reluctance motor” option2=”It is basically an induction motor and not a synchronous one” option3=”So far as its basic working principle is concerned, it is similar to shaded pole motor” option4=”the air-gap between rotor and salient poles is non- uniform” correct=”option4″]

Detailed SolutionWhich of the following statements regarding reluctance-start motor is incorrect ?

[amp_mcq option1=”it is comparatively cheaper” option2=”it has almost non-destructible capacitor” option3=”it has low starting as well as running currents at relatively high power factor” option4=”it is quiet in operation” correct=”option3″]

Detailed SolutionTwo-value capacitor motor finds increased application as compressor motor in small home air-conditioners because