Multiple Choice Questions on Transformer 19

  1. The magnetic flux of a transformer follows

    Under construction.

  2. The magnetizing current in a transformer is rich in

    Under construction.

  3. In a transformer zero voltage regulation is achieved at a load power factor which is of following ?

    Under construction.

  4. The inductive reactance of a transformer depends upon

    Under construction.

  5. A transformer has hysteresis loss of 30 W, at 240 V, 60 Hz. The hysteresis loss at 200 V, 50 Hz will be

    Under construction.

  6. Distribution transformer has core losses

    Under construction.

  7. In which transformer tertiary winding is used?

    Under construction.

  8. Noise level test conducted on a transformer is a

    Under construction.

  9. Auto transformer is preferred over an ordinary two winding transformer due to

    Under construction.

  10. A shell type transformer is commonly used as it has

    Under construction.

  11. The core used in high frequency transformer is ______________________ core.

    Under construction.

  12. A transformer with an output voltage 2400 V, is supplied at 230 V. If secondary has 2000 turns,calculate the number of primary turns

    Under construction.

  13. Keeping in view the requirement of parallel operation, which of the 3-phase connections given below are possible ?

    Under construction.

  14. The inductive reactance of a transformer depends upon

    Under construction.

  15. If P1 and P2 be the iron and copper losses of a transformer on full load, find the ratio of P1 and P2 such that maximum efficiency occurs at 75 % of full load

    Iron loss, Pi = P1, Cu loss at 75 % full load = x2Pc = ( 75 / 100)2P2. For maximum efficiency we have Pi = x2Pc
    ⇒ P1 / P2 = 9 / 16 = 0.5625.

  16. When a transformer winding suffers a short-circuit, the adjoining turns of the same windings experiences

    Under construction.

  17. The density of transformer oil is around

    Under construction.

  18. The flash point of transformer oil is usually

    Under construction.

  19. The dielectric strength of transformer oil should not be less than

    Under construction.

  20. What is the simplest transformer cooling arrangement?

    Under construction.