Chapter 3. Transformers
1. The primary and secondary of a transformer are ________ coupled but _______ connected.
(a) magnetically, not electrically
(b) electrically, not magnetically
(c) magnetically, also magnetically
(d) electrically, also electrically
Answer:Â Option(a)
2. The primary and secondary of a transformer are ________ coupled but _______ connected.
(a) magnetically, not electrically
(b) electrically, not magnetically
(c) magnetically, also magnetically
(d) electrically, also electrically
Answer: Option (a)
3. The primary and secondary of a transformer are ________ coupled but _______ connected.
(a) magnetically, not electrically
(b) electrically, not magnetically
(c) magnetically, also magnetically
(d) electrically, also electrically
Answer: Option (a)
4. The primary and secondary of a transformer are ________ coupled but _______ connected.
(a) magnetically, not electrically
(b) electrically, not magnetically
(c) magnetically, also magnetically
(d) electrically, also electrically
Answer: Option (a)
5. Core type transformers have, LV and HV windings are arranged such that
(a) Half LV near the core and half HV outside LV on each limb
(b) LV one one limb and HV on the other
(c) Half LV outside the core and half HV inside LV on each limb
(d) LV and HV windings are sandwiched
Answer:Â Option(a)
6. Core type transformers have, LV and HV windings are arranged such that
(a) Half LV near the core and half HV outside LV on each limb
(b) LV one one limb and HV on the other
(c) Half LV outside the core and half HV inside LV on each limb
(d) LV and HV windings are sandwiched
Answer: Option (a)
7. Core type transformers have, LV and HV windings are arranged such that
(a) Half LV near the core and half HV outside LV on each limb
(b) LV one one limb and HV on the other
(c) Half LV outside the core and half HV inside LV on each limb
(d) LV and HV windings are sandwiched
Answer: Option (a)
8. Core type transformers have, LV and HV windings are arranged such that
(a) Half LV near the core and half HV outside LV on each limb
(b) LV one one limb and HV on the other
(c) Half LV outside the core and half HV inside LV on each limb
(d) LV and HV windings are sandwiched
Answer: Option (a)
9. In an oil filled transformer, the application of oil is for
(a) cooling
(b) insulation
(c) both cooling and insulation
(d) preventing the accumulation of dust
Answer: Option (c)
10. In an oil filled transformer, the application of oil is for
(a) cooling
(b) insulation
(c) both cooling and insulation
(d) preventing the accumulation of dust
Answer: Option (c)
11. In an oil filled transformer, the application of oil is for
(a) cooling
(b) insulation
(c) both cooling and insulation
(d) preventing the accumulation of dust
Answer: Option (c)
12. In an oil filled transformer, the application of oil is for
(a) cooling
(b) insulation
(c) both cooling and insulation
(d) preventing the accumulation of dust
Answer: Option (c)
13. We laminate transformer core to reduce
(a) eddy current loss
(b) hysteresis loss
(c) both eddy current and hysteresis loss
(d) ohmic loss
Answer: Option (a)
14. We laminate transformer core to reduce
(a) eddy current loss
(b) hysteresis loss
(c) both eddy current and hysteresis loss
(d) ohmic loss
Answer:Â Option(a)
15. We laminate transformer core to reduce
(a) eddy current loss
(b) hysteresis loss
(c) both eddy current and hysteresis loss
(d) ohmic loss
Answer: Option (a)
16. We laminate transformer core to reduce
(a) eddy current loss
(b) hysteresis loss
(c) both eddy current and hysteresis loss
(d) ohmic loss
Answer:Â Option(a)
17. If a transformer is fed from a 220V and dc supply rather than a 1-phase ac supply, then the transformer will
(a) burn its windings
(b) operate normal
(c) will not operate
(d) will give very small leakage flux
Answer:Â Option(a)
18. If a transformer is fed from a 220V and dc supply rather than a 1-phase ac supply, then the transformer will
(a) burn its windings
(b) operate normal
(c) will not operate
(d) will give very small leakage flux
Answer: Option (a)
19. If a transformer is fed from a 220V and dc supply rather than a 1-phase ac supply, then the transformer will
(a) burn its windings
(b) operate normal
(c) will not operate
(d) will give very small leakage flux
Answer:Â Option(a)
20. If a transformer is fed from a 220V and dc supply rather than a 1-phase ac supply, then the transformer will
(a) burn its windings
(b) operate normal
(c) will not operate
(d) will give very small leakage flux
Answer: Option (a)
21. The flux involved in the emf equation of a transformer has
(a) rms value
(b) average value
(c) total value
(d) maximum value
Answer: Option (d)
22. The flux involved in the emf equation of a transformer has
(a) rms value
(b) average value
(c) total value
(d) maximum value
Answer: Option (d)
23. The flux involved in the emf equation of a transformer has
(a) rms value
(b) average value
(c) total value
(d) maximum value
Answer: Option (d)
24. The flux involved in the emf equation of a transformer has
(a) rms value
(b) average value
(c) total value
(d) maximum value
Answer:Â Option(d)
25. Power required during the open circuit and short circuit test is
(a) losses incurring in the transformer
(b) executing the power requirements by measuring instruments
(c) power for the core losses only
(d) all of the mentioned
Answer: Option (a)
26. Power required during the open circuit and short circuit test is
(a) losses incurring in the transformer
(b) executing the power requirements by measuring instruments
(c) power for the core losses only
(d) all of the mentioned
Answer:Â Option(a)
27. Power required during the open circuit and short circuit test is
(a) losses incurring in the transformer
(b) executing the power requirements by measuring instruments
(c) power for the core losses only
(d) all of the mentioned
Answer: Option (a)
28. Power required during the open circuit and short circuit test is
(a) losses incurring in the transformer
(b) executing the power requirements by measuring instruments
(c) power for the core losses only
(d) all of the mentioned
Answer: Option (a)
29. Which of the below mentioned losses occur in a transformer?
(a) Hysteresis losses ;Eddy current losses; Dielectric losses; Stray load losses
(b) Hysteresis losses ;Eddy current losses;
(c) Dielectric losses; Stray load losses
(d) Hysteresis losses ;Eddy current losses; Stray load losses
Answer: Option (a)
30. Which of the below mentioned losses occur in a transformer?
(a) Hysteresis losses ;Eddy current losses; Dielectric losses; Stray load losses
(b) Hysteresis losses ;Eddy current losses;
(c) Dielectric losses; Stray load losses
(d) Hysteresis losses ;Eddy current losses; Stray load losses
Answer: Option (a)
31. Which of the below mentioned losses occur in a transformer?
(a) Hysteresis losses ;Eddy current losses; Dielectric losses; Stray load losses
(b) Hysteresis losses ;Eddy current losses;
(c) Dielectric losses; Stray load losses
(d) Hysteresis losses ;Eddy current losses; Stray load losses
Answer: Option (a)
32. Which of the below mentioned losses occur in a transformer?
(a) Hysteresis losses ;Eddy current losses; Dielectric losses; Stray load losses
(b) Hysteresis losses ;Eddy current losses;
(c) Dielectric losses; Stray load losses
(d) Hysteresis losses ;Eddy current losses; Stray load losses
Answer:Â Option(a)
33. It is possible to attain maximum efficiency in a transformer when the
(a) core losses are equal to rated full load copper losses
(b) core losses are more than rated full load copper losses
(c) core losses and full load copper losses are constant
(d) copper loss also becomes constant
Answer: Option (a)
34. It is possible to attain maximum efficiency in a transformer when the
(a) core losses are equal to rated full load copper losses
(b) core losses are more than rated full load copper losses
(c) core losses and full load copper losses are constant
(d) copper loss also becomes constant
Answer: Option (a)
35. It is possible to attain maximum efficiency in a transformer when the
(a) core losses are equal to rated full load copper losses
(b) core losses are more than rated full load copper losses
(c) core losses and full load copper losses are constant
(d) copper loss also becomes constant
Answer: Option (a)
36. It is possible to attain maximum efficiency in a transformer when the
(a) core losses are equal to rated full load copper losses
(b) core losses are more than rated full load copper losses
(c) core losses and full load copper losses are constant
(d) copper loss also becomes constant
Answer: Option (a)
37. It is advised to coat the laminations of the core with some enamel, to ensure
(a) insulation
(b) adhesion of laminations
(c) reduction in humming sound
(d) all of the mentioned
Answer:Â Option(a)
38. It is advised to coat the laminations of the core with some enamel, to ensure
(a) insulation
(b) adhesion of laminations
(c) reduction in humming sound
(d) all of the mentioned
Answer: Option (a)
39. It is advised to coat the laminations of the core with some enamel, to ensure
(a) insulation
(b) adhesion of laminations
(c) reduction in humming sound
(d) all of the mentioned
Answer:Â Option(a)
40. It is advised to coat the laminations of the core with some enamel, to ensure
(a) insulation
(b) adhesion of laminations
(c) reduction in humming sound
(d) all of the mentioned
Answer: Option (a)