Transformers MCQ Questions & Answers | Electrical Engineering

11

Iron loss of a transformer can be measured by

A) low power factor wattmeter B) unity power factor wattmeter C) frequency meter D) any type of wattmeter

Discuss

Answer & Solution

Answer: Option A

No explanation is given for this question. Let's Discuss on Board

12

Efficiency of a power transformer is of the order of

A) 100 per cent B) 98 per cent C) 50 per cent D) 25 per cent

Discuss

Answer & Solution

Answer: Option B

No explanation is given for this question. Let's Discuss on Board

13

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

A) Mechanical strength B) Low hysteresis loss C) High thermal conductivity D) High permeability

Discuss

Answer & Solution

Answer: Option C

No explanation is given for this question. Let's Discuss on Board

14

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

A) Low hysteresis loss B) High permeability C) High thermal conductivity D) Adequate mechanical strength

Discuss

Answer & Solution

Answer: Option C

No explanation is given for this question. Let's Discuss on Board

15

Natural air cooling is generally restricted for transformers up to

A) 1.5 MVA B) 5 MVA C) 15 MVA D) 50 MVA

Discuss

Answer & Solution

Answer: Option A

No explanation is given for this question. Let's Discuss on Board

16

Reduction in core losses and increase in permeability are obtained with transformer employing

A) core built-up of laminations of cold rolled grain oriented steel B) core built-up of laminations of hot rolled sheet C) either of the above D) none of the above

Discuss

Answer & Solution

Answer: Option A

No explanation is given for this question. Let's Discuss on Board

17

Harmonics in transformer result in

A) Increased core losses B) Increased I²R losses C) Magnetic interference with communication circuits D) All of the above

Discuss

Answer & Solution

Answer: Option D

No explanation is given for this question. Let's Discuss on Board

18

The efficiency of a transformer, under heavy loads, is comparatively low because

A) copper loss becomes high in proportion to the output B) iron loss is increased considerably C) voltage drop both in primary and secondary becomes large D) secondary output is much less as compared to primary input

Discuss

Answer & Solution

Answer: Option A

No explanation is given for this question. Let's Discuss on Board

19

In a power or distribution transformer about 10 per cent end turns are heavily insulated

A) to withstand the high voltage drop due to line surge produced by the shunting capacitance of the end turns B) to absorb the line surge voltage and save the winding of transformer from damage C) to reflect the line surge and save the winding of a transformer from damage D) none of the above

Discuss

Answer & Solution

Answer: Option A

No explanation is given for this question. Let's Discuss on Board

20

Which winding in a transformer has more number of turns?

A) Low voltage winding B) High voltage winding C) Primary winding D) Secondary winding

Discuss

Answer & Solution

Answer: Option B

No explanation is given for this question. Let's Discuss on Board