1. If we interchange the supply terminals of an universal motor, then the rotor will
(a) fail to start.
(b) rotate in reverse direction.
(c) run in same direction.
(d) burn out.
Answer
2. When an universal motor is operating in no load condition, its speed is laminated by
(a) armature resistance.
(b) field resistance.
(c) winding and friction.
(d) armature reaction.
Answer
3. For starting a schrage motor, three phase supply is connected to
(a) stator.
(b) rotor.
(c) commutator.
(d) none of the above.
Answer
4. Linear induction motor is used in
(a) conveyors.
(b) elevators.
(c) Accelerator.
(d) traction.
Answer
5. In a hysteresis motor, the hysteresis losses at standstill condition are
(a) minimum.
(b) maximum.
(c) very high.
(d) same at all speed.
Answer
6. Reluctance motor operates on
(a) DC only.
(b) AC only.
(c) both DC and AC.
(d) none of the above.
Answer
7. When the armature reaction effect in and AC series motor increases, its speed is
(a) increases.
(b) decreases.
(c) remain unchanged.
(d) none of the have.
Answer
8. In hysteresis motor, the rotor carries a layer of special magnetic material that must have
(a) non magnetic nature.
(b) zero hysteresis loop.
(c) low hysteresis loop.
(d) high hysteresis loop.
Answer
9. Efficiency of a universal motor is more which operates on
(a) AC.
(b) DC.
(c) either AC or DC.
(d) none of the above.
Answer
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