field effect transistors fet MCQs – Page 2

Practise focused field effect transistors fet questions with marked answers for exam preparation and subject revision.

field effect transistors fet Mcqs

21. n a common-source JFET amplifier, the output voltage is _____________?
0

A. taken at the source

B. in phase with the input

C. 180o out of phase with the input

D. 90o out of phase with the input

22. If load resistance in the above question (Q.49) is removed, the output voltage will_____________?
0

A. increase

B. stay the same

C. decrease

D. be zero

23. If the gate of a JFET is made less negative, the width of the conducting channel__________________?
0

A. remains the same

B. is increased

C. none of the above

D. is decreased

24. In a JFET, when drain voltage is equal to pinch-off voltage, the depletion layers ______________?
0

A. none of the above

B. have moderate gap

C. almost touch each other

D. have large gap

25. The input impedance of a MOSFET is of the order of______________?
0

A. kO

B. several MO

C. O

D. a few hundred O

26. In a FET, there are _____________pn junctions at the sides?
0

A. four

B. three

C. two

D. five

27. In a certain common-source D-MOSFET amplifier, Vds =3.2 V r.m. and Vgs = 280 mV r.m.s. The voltage gain is_______________?
0

A. 8.75

B. 11.4

C. 1

D. 3.2

28. A certain common-source JFET has a voltage gain of 10. If the source bypass capacitor is removed, ______________?
0

A. the voltage gain will increase

B. the Q-point will shift

C. the voltage gain will decrease

D. the transconductance will increase

29. The pinch-off voltage in a JFET is analogous to _____________ voltage in a vacuum tube?
0

A. none of the above

B. anode

C. cathode

D. grid cut off

30. A MOSFET has______________ terminals?
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A. three

B. four

C. two

D. five

31. If the cross-sectional area of the channel in n-channel JEFT increases, the drain current _____________?
0

A. is decreased

B. remains the same

C. is increased

D. none of the above

32. A CS JFET amplifier has a load resistance of 10 kO , RD= 820O . If gm= 5mS and Vin= 500 mV, the output signal voltage is__________________?
0

A. 25 V

B. 1.89 V

C. 2.05 V

D. 0.5 V

33. Which of the following devices has the highest input impedance ?
0

A. ordinary transistor

B. Crystal diode

C. JFET

D. MOSFET

34. A JFET has ____________ power gain?
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A. very small

B. small

C. very high

D. none of the above

35. The input control parameter of a JFET is __________________?
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A. drain voltage

B. source voltage

C. gate voltage

D. gate current

36. The output characteristics of a JFET closely resemble the output characteristics of a ___________ valve?
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A. tetrode

B. triode

C. diode

D. pentode

37. A MOSFET differs from a JFET mainly because _________________?
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A. the MOSFET has two gates

B. none of the above

C. the JFET has a pn junction

D. of power rating

38. A certain p-channel E-MOSFET has VGS(th) = -2V. If VGS= 0V, the drain current is ____________?
0

A. ID(on)

B. IDSS

C. 0 mA

D. maximum

39. In class A operation, the input circuit of a JFET is ____________ biased?
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A. reverse

B. forward

C. not

D. none of the above

40. The transconductance of a JFET ranges from ________________?
0

A. above 1000 mA/V

B. 100 to 500 mA/V

C. 0.5 to 30 mA/V

D. 500 to 1000 mA/V

Showing 21 to 40 of 47 mcqs