Power Electronics MCQ #16

1) Which device is used to convert DC power into AC power?

      a) Inverter

      b) Rectifier

      c) Transformer

      d) Amplifier

2) _____ is defined as the ratio of RMS value of the AC component in the output to the average or DC component represent in the output.

      a) Transformer Utilisation Factor (TUF)

      b) Ripple Factor

      c) Diversity Factor

      d) Demand Factor

3) The circuit which is used to remove unwanted portion of the waveform, without distorting the remaining part of the waveform are called _____.

      a) Clippers circuit

      b) Clamper circuit

      c) Voltage doubler circuit 

      d) Voltage tripler circuit 

4) The circuit which is used to add a DC level as per the requirements to the AC output signal are called ______.

      a) Clippers circuit

      b) Clamper circuit

      c) Voltage doubler circuit 

      d) Voltage tripler circuit 

ANSWER: | 1-a | 2-b | 3-a | 4-b |

5) In NPN transistor, the emitter current (I_E) = _______

      a) IB + IC

      b) IB – IC

      c) IC – IB

      d) IB

6) In which region transistor works as an amplifier?

      a) Saturation region

      b) Cut-off region

      c) Active region

      d) None of the above

7) SCR has ____ junctions and _____ terminals.

      a) 2, 3

      b) 3, 3

      c) 3, 2

      d) 2, 2

8) In reverse blocking state of SCR, anode is biased ______ with respect to cathode.

      a) Negative

      b) Positive

      c) Positive or Negative

      d) Zero

ANSWER: | 5-a | 6-c | 7-b | 8-a |

9) In forward blocking state of SCR, anode is biased ______ with respect to the cathode.

       a) Negative

      b) Positive

      c) Positive or Negative

      d) Zero

10) In reverse blocking state of SCR, _____ junction in reverse biased and ______ junction in forward biased.

      a) J1, J2 and J3

      b) J3, J1 and J2

      c) J1 and J3, J2

      d) J1 and J2, J3

11) In forward blocking state of SCR, _____ junction in reverse biased and ______ junction in forward biased.

      a) J2, J1 and J3

      b) J3, J1 and J2

      c) J1 and J3, J2

      d) J1 and J2, J3

12) Turn off time of the SCR is ______.

      a) 1us to 10us

      b) 100us to 10ms

      c) 50us to 500us

      d) 5us to 50us

ANSWER: | 9-b | 10-c | 11-a | 12-d |

Power Electronics MCQ #15