THREE PHASE INDUCTION MOTORS QUIZ

None of the listed here

Cascade control

Pole changing

Rheostatic control

None of the listed here

Uniform torque

Less rotor losses

Greater mechanical strength

Cast iron

Carbon steel

High speed steel

Stainless steel

0.2

0.5

Practically zero

1

10 to 15%

5%

15 to 20 %

30 to 50%

0.2 leading

0.5 leading

Unity

0.2 lagging

Lower cage winding has low reactance

Lower winding is more effective

Outer cage winding has good pf

None of the listed here

Reducing supply voltage

Changing supply frequency

Changing winding resistance

Changing number of poles

K2 × torque with direct switching

K × torque with direct switching

k2/torque with direct switching

k/torque with direct switching

Very costly

Not easily maintainable

A variable speed motor

Essentially a constant speed motor