Important Electrical Machine Design Multiple Choice Questions and Answers

16.  A shaft may fail due to fatigue developed due to

   A. Stress concentration

   B. Presence of cyclic overloads

   C. Wrong adjustment of bearings,insufficient clearances etc.

   D. All of the above

17.  The critical speed of the shaft for an electric motor should be .........operating speed

   A. Exactly the same as

   B. Away from the

   C. Half of

   D. Double of

18. In .............. Machines the size (diameter) of the shaft is decided by the critical speed

   A. Small

   B. Medium

   C. Large

   D. Any of the above

19.  Shaft is designed satisfying the requirements

   A. Of sufficient strength of transmit torque at all loads without stress concentration

   B. Sufficiently rigid so that during operation the rotor does not touch the stator

   C. Critical speed of rotation must be different from the operating speeds of the machine

   D. All of the above

20.  The design of shaft for an electrical machine is determined by considerations of

   A. Ability to resist deflection due to weight of a rotor and unbalanced magnetic pull

   B. Strength to transmit power

   C.Both A or B

   D. None of the above

< 1 2 3 4 5 6 7 8 9 10 Next