The power factor is a ratio of real power and apparent power. Given below are top 10 MCQs on Power Factor.

1. Power factor can be mathematically expressed as:

  1. PF = P/S
  2. PF = S/P
  3. PF = P + S
  4. PF = P – S

Correct answer: 1

Power factor is a ratio of real power to apparent power


2. The power factor of an inductive circuit has:

  1. Leading
  2. Lagging
  3. Unity
  4. Any of above

Correct answer: 2

A purely inductive circuit has Lagging power factor


3. The power factor of purely resistive circuit is:

  1. Leading
  2. Lagging
  3. Unity
  4. Any of above

Correct answer: 3

The power factor of a purely resistive circuit is unity


4. The power factor of a capacitive load is:

  1. Leading
  2. Lagging
  3. Unity
  4. Any of above

Correct answer: 1

A purely capacitive load has leading power factor


5. A load having poor power factor draws current:

  1. Negligible
  2. Not negligible but small
  3. Normal
  4. High

Correct answer: 4


6. Practical loads are usually:

  1. Resistive
  2. Capacitive
  3. Inductive
  4. Resistive + Inductive

Correct answer: 4. Resistive + Inductive


7. Usually, the engineers achieve PF correction using:

  1. Capacitors
  2. Inductors
  3. Resistors
  4. All of above

Correct answer: 1. Capacitors


8. Power factor can be numerically measured as:

  1. A number
  2. Percentage
  3. Both of these
  4. None of these

Correct answer: 3. Both of these


9. If power factor is expressed as a number, the digit 1 indicates:

  1. Power factor is unity
  2. Power factor is only 1%
  3. Power factor is too poor
  4. None of above

Correct answer: 1


10. In purely resistive circuit:

  1. Current and Power are in phase
  2. Current and Power are out of phase
  3. Current leads by 30 degree
  4. Current lags by 55 degress

Correct answer: 1.