Top 350+ Solved Electrical Machine 1 MCQ Questions Answer

a. reduces generator e.m.f.

b. increases armature speed

c. reduces interpoles flux density

d. results in sparking trouble

a. electromagnets

b. permanent magnets

c. both (a) and (b)

d. none of the above

a. speed of armature

b. type of winding

c. voltage

d. amount of current to be collected

a. mainly to reduce the eddy currents by providing local short-circuits

b. to provide path for the circulation of cooling air

c. to neutralise the cross-magnetising effect of the armature reaction

d. none of the above

a. Dummy coils

b. Commutator

c. Eye bolt

d. Equilizer rings

a. using conductor of annealed copper

b. using commutator with large number of segments

c. using carbon brushes of superior quality

d. using equiliser rings

a. high voltage, high current

b. low voltage, high current

c. high voltage, low current

d. low voltage, low current

a. 2 : 3

b. 3 : 1

c. 3 : 2

d. 1 :3

a. Graphite brushes

b. Carbon brushes

c. Metal graphite brushes

d. None of the above

a. E/2

b. 2E

c. slightly less than E

d. E

a. silicon steel

b. copper

c. non-ferrous material

d. cast-iron

a. identified by the scarring of the commutator segment to which open circuited coil is connected

b. indicated by a spark completely around the commutator

c. both (a) and (b)

d. none of the above

a. voltage of the incoming generator should be same as that of bus bar

b. polarity of incoming generator should be same as that of bus bar

c. all the series fields should be run in parallel by means of equilizer connection

d. series fields of all generators should be either on positive side or negative side of the armature

a. to supply traction load

b. to supply industrial load at constant voltage

c. voltage at the toad end of the feeder

d. for none of the above purpose

a. series generator

b. shunt generator

c. compound generator

d. self-excited generator