# MCQs on Transformer Pdf | Online Test

A transformer is an electrical device that allows the voltage of an alternating current electrical circuit to be increased or decreased (there are no direct current transformers), it can also be used to electrically isolate a circuit. It is composed of two independent windings (windings) in a core of air or electromagnetic material.

The basic principle of operation is that putting an alternating current in the primary winding creates a magnetic flux in the core of the transformer, and therefore it is also created in the secondary winding. Consequently, a variable voltage is produced in the secondary winding, it can be higher or lower depending on the type of transformer.

To help you score in the upcoming board and other competitive exams like NEET, here is a list of some of the popular Multiple Choice Questions on Transformer mcqs pdf for class 12th that you can solve transformer  mcq online test and practice more for your upcoming exams.

If you are looking for Transformer Multiple Choice Questions for NEET. Here we collected some important MCQs on Transformer pdf for NEET. The Transformer mcqs pdf for class 12th included in this page have been selected based on the popular questions asked in various competitive exams over the years.

## MCQs on Transformer pdf for NEET

1. A transformer is used to convert______

(a) mechanical energy into electrical energy

(b) electrical energy into mechanical energy

(c) high (or low) voltage d.c. into low (or high) voltage d.c.

(d) high (or low) voltage a.c. into low (or high) voltage a.c.

2. The only quantity that remains constant in the operation of a transformer is________

(a) Voltage

(b) Current

(c) Frequency

(d) Turns ratio

3. The primary and secondary windings of a transformer are______

(a) electrically coupled

(b) magnetically coupled

(c) capacitively coupled

(d) inductively coupled

4. Which one of the following is not a basic part (element) of a transformer ?

(a) Core

(b) Primary winding

(c) Secondary winding

(d) Magnetic flux

5. In a step up transformer there is a decrease in the secondary.

(a) Voltage

(b) Current

(c) Power

(d) Frequency

6. In an ideal transformer, the primary and the secondary voltages always have__________

(a) equal magnitude

(b) the same phase

(c) a phase difference of 90°

(d) a phase difference of 180°

7. A transformer____________

(a) transforms energy

(b) transforms frequency

(c) generates an a.c.

(d) transtorms voltage

8. The output voltage ofa transformer does not depend upon the_________

(a) input voltage

(b) number of turns in the secondary

(c) number of turns in the primary

(d) frequency of A.C.

9. A transformer is used to reduce the mains supply of 220V to 22V. If the currents in the primary and secondary are 2A and 15A respectively, then the efficiency of the transformer is________

(a) 65%

(b) 75%

(c) 80%

(d) 90%

10. A step down transformer has a turn ratio of 5: 1. It is connected to 220 V, 50Hz ac mains supply. Secondary voltage and the frequency of secondary voltage are given by______

(a) 44 V, 10 Hz

(b) 110 V, 50 Hz

(c) 44 V, 50 Hz

(d) 1100 V, 10 Hz

11. The basic requirement for the operation of a transtormer is that its input voltage must be________

(a) Pulsating D.C. voltage

(b) Rectified

(c) Alternating

(d) Amplified

12. A transformer has 230 volts applied to the primary andd gives 4.6 V in the secondary. The secondary is connected
to a load which draws a current of 5 A. The current in the primary is________

(a) 1 A

(b) 0.1 A

(c) 2A

(d) 10 A

13. The core of a transformer is laminated__________

(a) to increase the secondary voltage

(b) to reduce the eddy current losses

(c) to give strength and to increase the life of the core

(d) to avoid the short circulating between the primary and secondary windings

14. In a transformer, if the voltage in the secondary is increased, then the current in the primary_________

(a) is increased

(b) is decreased

(c) does not change

(d) may increase or decrease

15. A shell-type transformer has__________

(a)high eddy current losses

(b) reduced magnetic leakage

(c) negligibly hysteresis losses

(d) none of the above

16. A transformer does not change the following________

(a) Waveform

(b) Frequency

(c) Voltage

(d) Both frequency and waveform

17. Generator transformers are________________

(a) Step-up transformers

(b) Step-down transformers

(c) Auto-transformers

(d) One-one transformers

18. In a transformer, the oil must be free from_________

(a) sulphur

(b) odour

(c) moisture

(d) both (a) and (c)

19. A transformer transforms________

(a) Current

(b) Voltage

(c) Frequency

(d) Both voltage and current

20. The no-load current of the transformer is usually what percent of its full load value:

(a) 2 to 5%

(b) 5 to 10%

(c) 10 to 20 %

(d) 0%

21. In an alternator one of the advantages of distributing the winding is to________

(a) Improve voltage waveform

(b) Reduce noise

(c) Same on copper

(d) Reduce harmonics

22. The transformer oil should have  _____ Volatility and _____ Viscosity.

(a) Low & High

(b) High & High

(c) Low & Low

(d) High & Low

23. Which type of winding is used in a 3-phase shell type transformer?

(a) Rectangular Type

(b) Cylindrical Type

(c) Sandwich Type

(d) Circular type

24. Impulse testing of transformers is done using_______

(a) Full wave standard impulse

(b) Chopped wave standard impulse

(c) Half wave standard impulse

(d) Only (a) and (b)