21. Light duty cranes are used in which of the following? A. Power houses B. Pumping stations C. Automobile workshops D. All of the above Answer & Solution Discuss in Board Save for Later Answer & Solution Answer: Option D No explanation is given for this question Let's Discuss on Board
22. The diameter of the rotor shaft for an electric motor depends on which of the following? A. r.p.m. only B. Horse power only C. Horse power and r.p.m. D. Horse power, r.p.m. and power factor Answer & Solution Discuss in Board Save for Later Answer & Solution Answer: Option C No explanation is given for this question Let's Discuss on Board
23. In case of __________ speed control by injecting e.m.f. in the rotor circuit is possible, A. D.C. shunt motor B. Schrage motor C. Synchronous motor D. Slip ring induction motor Answer & Solution Discuss in Board Save for Later Answer & Solution Answer: Option D No explanation is given for this question Let's Discuss on Board
24. Which of the following motors is preferred when smooth and precise speed control over a wide range is desired? A. D.C. motor B. Squirrel cage induction motor C. Wound rotor induction motor D. Synchronous motor Answer & Solution Discuss in Board Save for Later Answer & Solution Answer: Option A No explanation is given for this question Let's Discuss on Board
25. The selection of an electric motor for any application depends on which of the following factors? A. Electrical characteristics B. Mechanical characteristics C. Size and rating of motors D. All of the above Answer & Solution Discuss in Board Save for Later Answer & Solution Answer: Option D No explanation is given for this question Let's Discuss on Board
26. By the use of which of the following D.C. can be obtained from AC.? A. Silicon diodes B. Mercury arc rectifier C. Motor generator set D. Any of the above Answer & Solution Discuss in Board Save for Later Answer & Solution Answer: Option D No explanation is given for this question Let's Discuss on Board
27. Which of the following is essentially needed while selecting a motor? A. Pulley B. Starter C. Foundation pedal D. Bearings Answer & Solution Discuss in Board Save for Later Answer & Solution Answer: Option B No explanation is given for this question Let's Discuss on Board
28. Short time rated motors are preferred for overhead traveling cranes A. True B. False Answer & Solution Discuss in Board Save for Later Answer & Solution Answer: Option A No explanation is given for this question Let's Discuss on Board
29. Reluctance motor is a A. Variable torque motor B. Low torque variable speed motor C. Self starting type synchronous motor D. Low noise, slow speed motor Answer & Solution Discuss in Board Save for Later Answer & Solution Answer: Option C No explanation is given for this question Let's Discuss on Board
30. Which of the following types of motor enclosure is safest? A. Totally enclosed B. Totally enclosed fan cooled C. Open type D. Semi closed Answer & Solution Discuss in Board Save for Later Answer & Solution Answer: Option B No explanation is given for this question Let's Discuss on Board
