211. Starting winding of a single phase motor of a refrigerator is disconnected from the circuit by means of a
A. magnetic relay
B. thermal relay
C. centrifugal switch
D. none of the above
212. If a single phase induction motor runs slower than normal, the most likely defect is
A. warm bearings
B. short-circuit in the winding
C. open-circuit in the winding
D. none of the above
213. Which of the following motors is used in tape-recorders?
A. Hysteresis motor
B. Reluctance motor
C. Capacitor-run motor
D. Universal motor
214. Which of the following statements regarding two value capacitor motor is incorrect?
A. It is a reversing motor
B. It is preferred to permanent-split single-value capacitor motor where frequent reversais are required
C. It has low starting as well as rushing currents
D. It has high starting torque
215. Two-value capacitor motor finds increased application as compressor motor in small home air-conditioners because
A. it is comparatively cheaper
B. it has almost non-destructible capacitor
C. it has low starting as well as running currents at relatively high power factor
D. it is quiet in operation
216. 1f the centrifugal switch of a two-value capacitor motor using two capacitors fails to open then
A. motor will not come upto speed
B. motor will not carry the load
C. current drawn by the motor will be excessively high
D. electrolytic capacitor will, in all probability, suffer break down
217. In a universal motor, the most common cause of brush sparking is
A. open armature winding
B. shorted armature winding
C. shorted field winding
D. all of the above
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