In any rotating machine that part which houses the conductors and in which e.m.f. induced is to be utilized is called____________?

Related Mcqs:

1. According to Fleming’s right-hand rule for finding the direction of induced e.m.f., when middle finger points in the direction of induced e.m.f., forefinger will point in the direction of____________?

   A. motion of conductor
   B. lines of force
   C. either of the above
   D. none of the above

2. Eddy currents are induced in the pole shoes of a D.C. machine due to______________?

   A. oscillating magnetic field
   B. pulsating magnetic flux
   C. relative rotation between field and armature
   D. all above

3. For a D.C. generator when the number of poles and the number of armature conductors is fixed, then which winding will give the higher e.m.f___________ ?

   A. Lap winding
   B. Wave winding
   C. Either of A. and B. above
   D. Depends on other features of design

4. The commutator segments are connected to the armature conductors by means of___________?

   A. copper lugs
   B. resistance wires
   C. insulation pads
   D. brazing

5. In D.C. generators, the brushes on commutator remain in contact with conductors which_________________?

   A. lie under south pole
   B. lie under north pole
   C. lie under interpolar region
   D. are farthest from the poles

6. Fleming’s right-hand rule regarding direction of induced e.m.f., correlates__________?

   A. magnetic flux, direction of current flow and resultant force
   B. magnetic flux, direction of motion and the direction of e.m.f. induced
   C. magnetic field strength, induced voltage and current
   D. magnetic flux, direction of force and direction of motion of conductor

7. If B is the flux density, I the length of conductor and v the velocity of conductor, then induced e.m.f. is given by______________?

   A. Blv
   B. Blv2
   C. Bl2v
   D. Bl2v2

8. The e.m.f. induced in the armature of a shunt generator is 600 V. The armature resistance is 0.1 ohm. If the armature current is 200 A, the terminal voltage will be_____________?

   A. 640 V
   B. 620 V
   C. 600 V
   D. 580 V

9. In a D.C. generator in order to reduce sparking at brushes, the self-induced e.m.f. in the coil is neutralised by all of the following except______________?

   A. interpoles
   B. dummy coils
   C. compensating winding
   D. shifting of axis of brushes

10. If residual magnetism is present in a D.C. generator, the induced e.m.f. at zero speed will be____________?

    A. zero
    B. small
    C. the same as rated voltage
    D. high