Electrical Engineering Mcqs Practice Test

Question 1

Zener diode can be used as__________________?

Accepted Answer

C. both D.C and A.C voltage regulator

Question 2

The cold rolled grain oriented steel has _________ permeability in the direction of the grain orientation?

Accepted Answer

B. maximum

Question 3

Cylindrical windings using circular conductors, employed in transformers, are_____________?

Accepted Answer

C. multi-layered

Question 4

Multi-layer helical windings are commonly used in the transformers as high voltage windings_______________?

Accepted Answer

D. for 110 kV and above

Question 5

The cold rolled grain oriented steel has ___________ permeability in the direction of the grain orientation?

Accepted Answer

B. maximum

Question 6

Helical windings are used in________________?

Accepted Answer

B. power transformers

Question 7

Disc windings are primarily used in_____________-?

Accepted Answer

C. high capacity transformers

Question 8

The forced oil and air circulation method is usual one for transformers of capacities____________?

Accepted Answer

D. 30 MVA upwards

Question 9

The heat dissipating capability of transformers of ratings higher than 30 kVA in increased by providing which of the following ?

Accepted Answer

E. All of the above

Question 10

Transformers with a capacity of up to __________ have a cooling radiator system with natural cooling?

Accepted Answer

D. 10 MVA

Question 11

The voltage control in electric supply networks in required on account of which of the following reasons ?

Accepted Answer

D. All of the above

Question 12

Which of the following is the basic consideration in the design of insulation ?

Accepted Answer

D. All of the above

Question 13

A current density of __________ is ilsed for large power transformers with forced circulation of oil or with water cooling coils?

Accepted Answer

D. 5.4 to 6.2 A/mm2

Question 14

For 275 kV transformers, using cold rolled grain oriented steel, which of the following values of flux density may be used?

Accepted Answer

D. 1.6 Wb/m2

Question 15

D.C. windings are____________?

Accepted Answer

C. always 2-layer type

Question 16

The high voltage winding is usually which of the following type  ?

Accepted Answer

D. All of the above types

Question 17

The flash point of transformer oil should be higher than_______________?

Accepted Answer

D. 104°C

Question 18

The usual values of maximum flux densities for distribution transformers using hot rolled silicon steel are______________?

Accepted Answer

C. 1.1 to 1.35 Wb/m2

Question 19

For large power transformers, self oil cooled type or air blast type which of the following values of current density may be used?

Accepted Answer

C. 2.2 to 3.2 A/mm2

Question 20

A practical formula for determining the thickness of insulation between low voltage and high voltage windings is__________________?

Accepted Answer

D. 5 + 0.9 kV mm