Which of the following statements regarding hysteresis motor is in incorrect ?
It accelerates from rest to full-speed almost instantaneously
It is extremely sensitive to fluctuations in supply voltage
Its high starting torque is due to its high rotor hysteresis loss
It is extremely quiet in operation
It is extremely sensitive to fluctuations in supply voltage
Which of the following statements regarding a reluctance motor is incorrect ?
It cannot be reversed ordinarily
It requires no D.C. field excitation for its operation
It is nothing else but a single-phase salient pole synchronous-induction motor
Its squirrel cage-rotor is of unsymmetrical magnetic construction in order to vary reluctance path between stator and rotor
It cannot be reversed ordinarily
A universal motor is one which
none of the above
runs at dangerously high speed on no-load
can be marketed internationally
can be operated either on D.C. or A.C. supply at approximately the same speed and output
can be operated either on D.C. or A.C. supply at approximately the same speed and output
A repulsion motor is equipped with
slip rings
both and
commutator
none of the above
commutator
The starting winding of a single-phase motor is placed in
stator
rotor
field
armature
stator
The speed of a universal motor is usually reduced by using
gearing
brakes
belts
chains
gearing
If the centrifugal switch does not open at 70 to 80 percent of synchronous speed of motor it would result in
none of the above
damage to the starting winding
damage to the centrifugal switch
overloading of running winding
damage to the starting winding
Speed torque characteristic of a repulsion induction motor is similar to that of a D.C.
compound motor
4
2
1
compound motor
Speed control of a universal motor is achieved by
applying variable voltage by means of silicon controlled rectifier
connecting rheostat in series
varying field flux with tapped field windings
All
All
A shaded pole motor does not possess
centrifugal switch
capacitor
all of the above
commutator
all of the above
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