267. For a system involving sound recording and reproduction which motor would you select?
A. Shaded-pole motor
B. Universal motor
C. Reluctance motor
D. Hysteresis motor
268. For the same rating which of the following motors has the highest starting torque?
A. Synchronous motor
B. Universal motor
C. Split-phase motor
D. All have identical starting torque
269. A capacitor selected for capacitor-run motor should be rated for
A. r.m.s. voltage
B. average voltage
C. peak voltage
D. none of the above
270. If the ceiling fan, when switched on, runs at slow speed in the reverse direction, it can be concluded that
A. capacitor is ineffective
B. winding has burnt out
C. bearings are worn out
D. none of the above
271. By pushing and pulling the rotor shaft of a motor, we can check its
A. end play
B. side play
C. firmness of mounting
D. free shaft movement
272. Electrical faults in a motor occur most commonly in its
A. motor winding
B. commutator
C. control equipment
D. brushes
273. Which of the following statements regarding repulsion induction motor is incorrect?
A. At rated load, it runs at almost synchronous speed
B. It employs centrifugally-operated mechanism to short-circuit the commutator
C. At start as well as a low speeds, most of the torque is produced by repulsion winding
D. At starting, squirrel-cage winding produces no torque.
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