Basic Electrical Engineering MCQ- 2|Industries Extension Officer|Polytechnic lecturer|SSC JE|RRB JE

Basic Electrical Engineering MCQ- 2

11. While applying Fleming's right-hand rule to And the direction of induced e.m.f., the

thumb points towards

(a) direction of induced e.m.f.

(b) direction of flux

e.m.f.

(d) direction of motion of conductor, if forefinger points along the lines of flux

Ans: d

12. The bearings used to support the rotor shafts are generally

(a) ball bearings

(b) bush bearings

(d) needle bearings

Ans: a

13. In D.C. generators, the cause of rapid brush wear may be

(a) severe sparking

(b) rough commutator surface

(d) any of the above

Ans: d

14. In lap winding, the number of brushes is always

(a) double the number of poles

(b) same as the number of poles

(d) two

Ans: b

15. 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

(d) Depends on other features of design

Ans: b

16. In a four-pole D.C. machine

(a) all the four poles are north poles

(b) alternate poles are north and south

(d) two north poles follow two south poles

Ans: b

17. Copper brushes in D.C. machine are used

(a) where low voltage and high currents are involved

(b) where high voltage and small cur-rents are involved

(d) in none of the above cases

Ans: a

18. A separately excited generator as compared to a self-excited generator

(a) is amenable to better voltage con-trol

(b) is more stable

(d) has all above features

Ans: d

19. In case of D.C. machines, mechanical losses are primary function of

(a) current

(b) voltage

(d) none of above

Ans: c

20. Iron losses in a D.C. machine are independent of variations in

(a) speed

(b) load

(d) speed and voltage

Ans: b

Join Telegram HERE

Basic Electrical Engineering MCQ- 2|Industries Extension Officer|Polytechnic lecturer|SSC JE|RRB JE