# Power semiconductor devices - Electrical Engineering (MCQ) questions and answers

1)   In ac - dc conversion, when the switch is closed then the sum of voltages around the loop is

a. Zero
b. Non zero
c. Equal to the sum of voltage when switch is open
d. Twice of the voltage when switch is open
 Answer  Explanation ANSWER: Non zero Explanation: No explanation is available for this question!

2)   The switching function of semiconductor devices can be characterized with

a. Duty ratio only
b. Frequency only
c. Duty ratio and frequency
d. Duty ratio, frequency and time delay
 Answer  Explanation ANSWER: Duty ratio, frequency and time delay Explanation: No explanation is available for this question!

3)   The quadrant operation of BJT is represented by a. 1
b. 2
c. 3
d. 4
 Answer  Explanation ANSWER: 2 Explanation: No explanation is available for this question!

4)   TRIAC is a semiconductor power electronic device which contains

a. Two SCR’s connected in reverse parallel
b. Two SCR’s connected in parallel
c. Two SCR’s connected in series
d. Two BJT’s connected in series
 Answer  Explanation ANSWER: Two SCR’s connected in reverse parallel Explanation: No explanation is available for this question!

5)   Silicon controlled rectifier can be turned on

a. By applying a gate pulse and turned off only when current becomes zero
b. And turned off by applying gate pulse
c. By applying a gate pulse and turned off by removing the gate pulse
d. By making current non zero and turned off by making current zero
 Answer  Explanation ANSWER: By applying a gate pulse and turned off only when current becomes zero Explanation: No explanation is available for this question!

6)   Bidirectional semiconductor device is

a. Diode
b. BJT
c. SCR
d. TRIAC
 Answer  Explanation ANSWER: TRIAC Explanation: No explanation is available for this question!

7)   An ideal diode is

a. Unidirectional
b. Bidirectional
c. Fixed voltage polarity
d. Only (a) and (c)
 Answer  Explanation ANSWER: Only (a) and (c) Explanation: No explanation is available for this question!

8)   IGBT stands for

a. Insulated gate bipolar transistor
b. Insulated gate bidirectional transistor
c. Inductive gate bipolar transistor
d. Inductive gate bidirectional transistor
 Answer  Explanation ANSWER: Insulated gate bipolar transistor Explanation: No explanation is available for this question!

9)   An ideal switch is

a. Lossless
b. Carry current in any direction when it is on
c. Does not carry any current in any direction when it is off
d. All of these
 Answer  Explanation ANSWER: All of these Explanation: No explanation is available for this question!

10)   A rectifier with an external low pass filter is an example of

a. Indirect switch matrix circuits
b. Direct switch matrix circuits
c. Embedded converters
d. All of these
 Answer  Explanation ANSWER: Direct switch matrix circuits Explanation: No explanation is available for this question!