Electrical Engineering Mcqs Practice Test

Question 1

Noise level test in a transformer is a______________?

Accepted Answer

C. type test

Question 2

In an actual transformer the iron loss remains practically constant from no load to full load because:____________?

Accepted Answer

C. core flux remains practically constant

Question 3

The path of the magnetic flux in transformer should have____________?

Accepted Answer

B. low reactance

Question 4

When a given transformer is run at its rated voltage but reduced frequency, its____________?

Accepted Answer

D. core flux density is increased

Question 5

Which of the following properties is not necessarily desirable for the material for transformer core ?

Accepted Answer

C. High thermal conductivity

Question 6

The leakage flux in a transformer depends upon______________?

Accepted Answer

A. load current

Question 7

An ideal transformer is one which has_____________?

Accepted Answer

A. no losses and magnetic leakage

Question 8

Which of the following does not change in an ordinary transformer ?

Accepted Answer

A. Frequency

Question 9

The changes in volume of transformer cooling oil due to variation of atmospheric temperature during day and night is taken care of by which part of transformer?

Accepted Answer

A. Conservator

Question 10

The magnetising current of a transformer is usually small because it has___________?

Accepted Answer

A. small air gap

Question 11

Buchholz’s relay gives warning and protection against_________________?

Accepted Answer

A. electrical fault inside the transformer itself

Question 12

Two transformers are connected in parallel. These transformers do not have equal percentage impedance. This is likely to result in____________?

Accepted Answer

D. loading of the transformers not in proportion to their kVA ratings

Question 13

During short circuit test iron losses are negligible because of _____________?

Accepted Answer

C. the voltage applied on primary side is low

Question 14

Which of the following is the main advantage of an auto-transformer over a two winding transformer?

Accepted Answer

B. Saving in winding material

Question 15

Power transformers are generally designed to have maximum efficiency around__________?

Accepted Answer

C. near full-load

Question 16

Which winding of the transformer has less cross-sectional area?

Accepted Answer

D. High voltage winding

Question 17

Silicon steel used in lamination’s mainly reduces___________?

Accepted Answer

A. hysteresis loss

Question 18

Delta/star transformer works satisfactorily when______________?

Accepted Answer

C. on balanced as well as unbalanced loads

Question 19

Star/star transformers work satisfactorily when________________?

Accepted Answer

B. load is balanced only

Question 20

Which of the following property is not necessarily desirable in the material for transformer core ?

Accepted Answer

C. High thermal conductivity