Explore topic-wise MCQs in Power Electronics.

This section includes 9 Mcqs, each offering curated multiple-choice questions to sharpen your Power Electronics knowledge and support exam preparation. Choose a topic below to get started.

1.

Let’s say that a transistor is operating at the middle of the load line, then a decrease in the current gain would$#

A. move the Q point up
B. move the Q point down
C. result in to & fro motion of the Q point
D. not change the Q point
Answer» C. result in to & fro motion of the Q point
2.

Which of the following relations is true for a BJT?

A. Ic ≈ Ie
B. Ib ≈ Ic
C. Ie ≈ Ib
D. Ib ≈ Ie ≈ Ic
Answer» B. Ib ‚Äö√Ñ√∂‚àö¬¢‚àö‚Ć Ic
3.

A 1mv of i/p gives an output of 1V, the voltage gain as such would be

A. 0.001
B. 0.0001
C. 1000
D. 100
Answer» D. 100
4.

For a power transistor, the average power loss during the delay time can be given by the equation

A. Ic * Vc
B. 1/T * ‚à´<sup>Td</sup> (Ic Vce) dt
C. Ic * dVc/dt * T
D. 1/T * ‚à´<sup>(Td *Tr)</sup> (Ic Vc) dt
Answer» C. Ic * dVc/dt * T
5.

The instantaneous power loss during the delay time of a transistor is given by

A. Ic Vce
B. Ib Vbe
C. Ic Vbe
D. Ib Vce
Answer» B. Ib Vbe
6.

High frequency operation of any device is limited by the

A. forward voltage rating
B. switching losses
C. thermal conductivity
D. heat Sink arrangements
Answer» C. thermal conductivity
7.

For a power transistor, which of the following relations is true?

A. Ie>Ic>Ib
B. Ib>Ic>Ie
C. Ic>Ie>Ib
D. Ie=Ib
Answer» B. Ib>Ic>Ie
8.

The power electronics devices have a very high efficiency because

A. cooling is very efficient
B. the devices traverse active region at high speed & stays at the two states, on and off
C. the devices never operate in active region
D. the devices always operate in the active region
Answer» C. the devices never operate in active region
9.

For a power transistor, if the forward current gain α = 0.97, then β = ?

A. 0.03
B. 2.03
C. 49.24
D. 32.33
Answer» E.