A. motion of conductor
B. lines of force
C. either of the above
D. none of the above
D.C. Generators
D.C. Generators
A. direction of induced e.m.f.
B. direction of flux
C. direction of motion of the conductor if forefinger points in the direction of generated e.m.f.
D. direction of motion of conductor, if forefinger points along the lines of flux
A. rivets
B. counter sunk screws
C. brazing
D. welding
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
A. current
B. voltage
C. speed
D. none of above
A. where low voltage and high currents are involved
B. where high voltage and small cur-rents are involved
C. in both of the above cases
D. in none of the above cases
A. Lap winding
B. Wave winding
C. Either of A. and B. above
D. Depends on other features of design
A. severe sparking
B. rough commutator surface
C. imperfect contact
D. any of the above
A. ball bearings
B. bush bearings
C. magnetic bearmgs
D. needle bearings
A. double the number of poles
B. same as the number of poles
C. half the number of poles
D. two