A. rivets
B. counter sunk screws
C. brazing
D. welding
Related Mcqs:
- Two generators are running in parallel. One of the generators may run as motor for which of the following reasons ?
A. The direction of that generator is reversed
B. The speed of that generator is increased
C. The field of that generator is weakened
D. That generator takes large share of loads - 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 - The function of pole shoes in the case of D.C. machine is______________?
A. to reduce the reluctance of the mag¬netic path
B. to spread out the flux to achieve uniform flux density
C. to support the field coil
D. to discharge all the above functions - In case of a 4-pole D.C. generator provided with a two layer lap winding with sixteen coils, the pole pitch will be__________________?
A. 4
B. 8
C. 16
D. 32 - In D.C. generators, the cause of rapid brush wear may be___________?
A. severe sparking
B. rough commutator surface
C. imperfect contact
D. any of the above - Which of the following statement about D.C. generators is false ?
A. Compensating winding in a D.C. machine helps in commutation
B. In a D. C. generator interpoles winding is connected in series with the armature winding
C. Back pitch and front pitch are both odd and approximately equal to the pole pitch
D. Equilizing bus bars are used with parallel running of D.C. shunt gen¬erators - Which of the following D.C. generators will be in a position to build up without any residual magnetism in the poles?
A. Series generator
B. Shunt generator
C. Compound generator
D. None of the above - In D.C. generators the polarity of the interpoles_____________?
A. is the same as that of the main pole ahead
B. is the same as that of the immediately preceding pole
C. is opposite to that of the main pole ahead
D. is neutral as these poles do not play part in generating e.m.f. - Which of the following generators will be preferred if they are required to be run in parallel?
A. Shunt generators
B. Series generators
C. Compound generators
D. None of the above - Two D.C. shunt generators, each with armature resistance of 0.02 ohm and field resistance of 50 ohm run in parallel and supply a total current of 1000 amperes to the load circuit. If their e.m.fs. are 270 V and 265 V, their bus bar voltage will be_____________________?
A. 270 V
B. 267.5 V
C. 265 V
D. 257.4 V
