Transformers MCQ Quiz - Multiple Choice Questions & Answers Page 2

11. In an ideal transformers primary and secondary induced emfs are

1. self induced emfs
2. mutually induced emfs
3. self and mutually induced emfs respectively
4. mutually and self induced emfs respectively

12. The input power under no load condition of transformer consists of

1. core losses in transformer
2. core losses and very small amount of copper loss in primary
3. copper loss in transformers
4. significant copper loss along with negligible core losses

13. In a transformer the coils of primary and secondary are placed concentrically to achieve

1. reduced leakage flux between primary and secondary winding
2. reduced copper losses in the winding
3. reduced insulation cost of the windings
4. reduced voltage per turn in the winding

14. Iron loss in transformer can be determined by

1. short circuit test
2. open circuit test
3. both short circuit and open circuit tests
4. none of the above

15. No load losses in a transformer can be minimized by using steel of

1. high silicon content and very thin lamination
2. only high silicon content
3. only very thin lamination
4. low silicon content and very thin lamination

16. Which of the following losses remain constant during normal operation of transformer?

1. Copper loss
2. Stray loss
3. Core loss
4. All losses in transformer vary with load

17. Which of the following losses varies with load in transformer?

1. Copper loss
2. Hysteresis loss
3. Eddy current loss
4. All losses in transformer vary with load

18. What will be the eddy current loss if the supply frequency of a transformer becomes double?

1. Eight times
2. Four times
3. Doubled
4. Remains same

19. If the supply frequency of a transformer increases then output voltage of the transformer will

1. decrease
2. increase proportionately
3. remain same
4. increases very rapidly

20. In a core type transformer

1. HV winding is placed nearer to the core limb
2. LV winding is placed nearer to the core limb
3. any of the LV or HV can be placed nearer to the core limb
4. HV and LV windings are placed in different core limbs