Power Electronics MCQs Quizlet (Bank of Solved Questions Answers)

1. : What is the typical value of SCR for a modern alternator?
(A) 0.5
(B) 1.5
(C) 1.0
(D) 1.2

2. : If the input voltage is 110 V and the output voltage is 150 V of a step-up chopper, what is the value of duty cycle?
(A) 0.45
(B) 0.27
(C) 0.32
(D) 0.67

3. : During the forward blocking mode of a thyristor, which junction is in reverse bias?
(A) Junction J3 is forward biased and J1, J2 are reverse biased
(B) Junction J2 is in reverse bias and J1, J3 are forward biased
(C) Junction J1 and J2 are forward biased and J3 is reverse biased
(D) Junction J1, J3 are reverse biased and J2 is forward biased

4. : Which of the following devices does not belong to the transistor family?
(A) MOSFET
(B) IGBT
(C) BJT
(D) GTO

5. : A power transistor is a ____ device.
(A) Three-layer, three-junction device
(B) Two-layer, one-junction device
(C) Three-layer, two-junction device
(D) Four-layer, three-junction device

6. : In a power transistor, which parameter is controlled?
(A) IC
(B) IB
(C) VCE
(D) VBE

7. : A power transistor is a device which is:
(A) Two-terminal, bipolar, voltage-controlled
(B) Three-terminal, bipolar, current-controlled
(C) Three-terminal, unipolar, voltage-controlled
(D) Two-terminal, unipolar, current-controlled

8. : The IB vs VBE curve of a power transistor is:
(A) Resembling the diode curve
(B) An exponentially decaying curve
(C) A parabolic curve
(D) A straight line Y = IB

9. : The forward current gain α is given by:
(A) IC / IB
(B) IE / IB
(C) IE / IC
(D) IC / IE

10. : Power loss will be maximum when:
(A) Both V and I are minimum
(B) Only V is maximum
(C) Both V and I are maximum
(D) Only I is maximum

11. : In an AC-DC converter, a diode might be used as:
(A) A freewheeling diode
(B) A filter
(C) A voltage source
(D) A phase-angle controller

12. : A p-n junction diode is forward biased when the width of the depletion region:
(A) Remains constant
(B) Increases
(C) Decreases
(D) First increases then decreases