Explore topic-wise MCQs in Testing Subject.

This section includes 657 Mcqs, each offering curated multiple-choice questions to sharpen your Testing Subject knowledge and support exam preparation. Choose a topic below to get started.

1.

The transconductance of a JFET ranges from ___________$?

A. 100 to 500 mA/V
B. 500 to 1000 mA/V
C. 0.5 to 30 mA/V
D. above 1000 mA/V
Answer» D. above 1000 mA/V
2.

A certain common source JFET has a voltage gain of 10. If the source bypass capacitor is removed, ___________$?

A. the voltage gain will increase
B. the transconductance will increase
C. the voltage gain will decrease
D. the Q-point will shift
Answer» D. the Q-point will shift
3.

In a JFET, when drain voltage is equal to pinch-off voltage, the depletion layers$?

A. almost touch each other
B. have large gap
C. have moderate gap
D. none of the above
Answer» B. have large gap
4.

If the cross-sectional area of the channel in n-channel JEFT increases, the drain current ___________$?

A. is increased
B. is decreased
C. remains the same
D. none of the above
Answer» B. is decreased
5.

A MOSFET uses the electric field of a ___________ to control the channel current$?

A. capacitor
B. battery
C. generator
D. none of the above
Answer» B. battery
6.

The output characteristics of a JFET closely resemble the output characteristics of a ___________ valve$?

A. pentode
B. tetrode
C. triode
D. diode
Answer» B. tetrode
7.

The output characteristics of a JFET closely resemble the output characteristics of a ___________ valve?

A. pentode
B. tetrode
C. triode
D. diode
Answer» B. tetrode
8.

A JFET has ___________ power gain

A. small
B. very high
C. very small
D. none of the above
Answer» C. very small
9.

At cut-off, the JFET channel is ___________

A. at its widest point
B. completely closed by the depletion region
C. extremely narrow
D. reverse baised
Answer» C. extremely narrow
10.

Which of the following devices has the highest input impedance?

A. JFET
B. MOSFET
C. Crystal diode
D. ordinary transistor
Answer» C. Crystal diode
11.

The input impedance of a MOSFET is of the order of ___________

A. O
B. a few hundred O
C. kΩ
D. several MO
Answer» E.
12.

A MOSFET can be operated with ___________

A. negative gate voltage only
B. positive gate voltage only
C. positive as well as negative gate voltage
D. none of the above
Answer» D. none of the above
13.

If the gate of a JFET is made less negative, the width of the conducting channel ___________

A. remains the same
B. is decreased
C. is increased
D. none of the above
Answer» D. none of the above
14.

The input impedance of a JFET is ___________ that of an ordinary transistor

A. equal to
B. less than
C. more than
D. none of the above
Answer» D. none of the above
15.

The gate voltage in a JFET at which drain current becomes zero is called ___________ voltage

A. saturation
B. pinch-off
C. active
D. cut-off
Answer» C. active
16.

A JFET is a ___________ driven device

A. current
B. voltage
C. both current and voltage
D. none of the above
Answer» C. both current and voltage
17.

The pinch-off voltage in a JFET is analogous to ___________ voltage in a vacuum tube

A. anode
B. cathode
C. grid cut off
D. none of the above
Answer» D. none of the above
18.

___________ has the lowest noise-level

A. triode
B. ordinary trnsistor
C. tetrode
D. JFET
Answer» E.
19.

In a FET, there are ___________ pn junctions at the sides

A. three
B. four
C. five
D. two
Answer» E.
20.

In class A operation, the input circuit of a JFET is ___________ biased

A. forward
B. reverse
C. not
D. none of the above
Answer» C. not
21.

If the reverse bias on the gate of a JFET is increased, then width of the conducting channel ___________

A. is decreased
B. is increased
C. remains the same
D. none of the above
Answer» B. is increased
22.

The input control parameter of a JFET is ___________

A. gate voltage
B. source voltage
C. drain voltage
D. gate current
Answer» B. source voltage