The efficiency of two identical transformers under load conditions can be determined by_______________?

Related Mcqs:

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

   A. short-circuiting of the secondaries
   B. power factor of one of the transformers is leading while that of the other lagging
   C. transformers having higher copper losses will have negligible core losses
   D. loading of the transformers not in proportion to their kVA ratings

2. Power transformers are designed to have maximum efficiency at___________?

   A. nearly full load
   B. 70% full load
   C. 50% full load
   D. no load

3. Distribution transformers are generally designed for maximum efficiency around________________?

   A. 90% load
   B. zero load
   C. 25% load
   D. 50% load

4. Power transformers are generally designed to have maximum efficiency around__________?

   A. no-load
   B. half-load
   C. near full-load
   D. 10% overload

5. Two transformers operating in parallel will share the load depending upon their____________?

   A. leakage reactance
   B. per unit impedance
   C. efficiencies
   D. ratings

6. An ideal transformer will have maximum efficiency at a load such that?

   A. copper loss = iron loss
   B. copper loss iron loss
   D. none of the above

7. For a transformer, operating at constant load current, maximum efficiency will occur at______________?

   A. 0.8 leading power factor
   B. 0.8 lagging power factor
   C. zero power factor
   D. unity power factor

8. Sumpner’s test is conducted on transformers to determine_____________?

   A. temperature
   B. stray losses
   C. all-day efficiency
   D. none of the above

9. If the percentage impedances of the two transformers working in parallel are different, then______________________?

   A. transformers will be overheated
   B. power factors of both the transformers will be same
   C. parallel operation will be not possible
   D. parallel operation will still be possible, but the power factors at which the two transformers operate will be different from the power factor of the common load

10. For the parallel operation of single phase transformers it is necessary that they should have___________?

    A. same efficiency
    B. same polarity
    C. same kVA rating
    D. same number of turns on the secondary side.