For given applied voltage, with the increase in frequency of the applied voltage?

Related Mcqs:

1. In a given transformer for given applied voltage, losses which remain constant irrespective of load changes are______________?

   A. friction and windage losses
   B. copper losses
   C. hysteresis and eddy current losses
   D. none of the above

2. In a given transformer for a given applied voltage, losses which remain constant irrespective of load changes are__________?

   A. hysteresis and eddy current losses
   B. friction and windage losses
   C. copper losses
   D. none of the above

3. When a given transformer is run at its rated voltage but reduced frequency, its____________?

   A. flux density remains unaffected
   B. iron losses are reduced
   C. core flux density is reduced
   D. core flux density is increased

4. The no load current in a transformer lags behind the applied voltage by an angle of about_____________?

   A. 180°
   B. 120″
   C. 90°
   D. 75°

5. The core used in high frequency transformer is usually___________?

   A. copper core
   B. cost iron core
   C. air core
   D. mild steel core

6. If the supply frequency to the transformer is increased,”the iron loss will__________?

   A. not change
   B. decrease
   C. increase
   D. any of the above

7. A transformer cannot raise or lower the voltage of a D.C. supply because_______________?

   A. there is no need to change the D.C. voltage
   B. a D.C. circuit has more losses
   C. Faraday’s laws of electromagnetic induction are not valid since the rate of change of flux is zero
   D. none of the above

8. Negative voltage regulation is indicative that the load is___________?

   A. capacitive only
   B. inductive only
   C. inductive or resistive
   D. none of the above

9. If a transformer is switched on to a voltage more than the rated voltage______________?

   A. its power factor will deteriorate
   B. its power factor will increase
   C. its power factor will remain unaffected
   D. its power factor will be zero

10. Minimum voltage regulation occurs when the power factor of the load is_____________?

    A. unity
    B. lagging
    C. leading
    D. zero