D.C. machines designed with a large value of air gap length have_____________?

Related Mcqs:

1. The operation of a D.C. machine with large air gap lengths is comparatively_____________?

   A. quiet B. noisy C. either of the above D. none of the above...

2. In induction motors, the length of air gap in kept as small as mechanically possible is order to have____________?

   A. low power factor B. high power factor C. high over load capacity D. any of the above...

3. The length cf air gap to be provided in __________ is primarily determined by power factor consideration?

   A. d.c. series motor . B. d.c. shunt motor C. induction motor D. synchronous motor...

4. In D.C. machines, the ________ in field mmf results in increase in size and cost of machines?

   A. increase B. decrease C. either of the above D. none of the above...

5. Multiple inlet system of air cooling of turbo-alternators can be used for machines of rating upto_______________?

   A. 10 MW B. 30 MW C. 60 MW D. 150 MW...

6. In _________ machines, the size of the shaft is decided by the critical speed which depends on the deflection of the shaft?

   A. small B. medium C. large D. any of the above....

7. The action of electromagnetic machines can be related to which of the following basic principles __________?

   A. Induction B. Interaction C. Alignment D. All of the above...

8. _______________is universally used for windings of electrical machines because it is easily workable without any possibility of fracture?

   A. Silver B. Steel C. Aluminium D. Copper...

9. In D.C. machines the width of the duct is usually_____________?

   A. 4 mm B. 6 mm C. 8 mm D. 10 mm...

10. In D.C. machines the usual limit of slot pitch is________________?

    A. between 5 to 10 mm B. between 10 to 15 mm C. between 15 to 20 mm D. between 25 to 35 mm...