Fet Field Effect Transistors(Engineering > Electrical Engineering ) Questions and Answers
Question 1. The gate voltage in a JFET at which drain current becomes zero is called ___________ voltage
saturation
pinch-off
active
cut-off
Explanation:-
Answer: Option B. -> pinch-off
Question 2. The output characteristics of a JFET closely resemble the output characteristics of a ___________ valve
pentode
tetrode
triode
diode
Explanation:-
Answer: Option A. -> pentode
Question 3. The constant-current region of a JFET lies between
cut off and saturation
cut off and pinch-off
o and IDSS
pinch-off and breakdown
Explanation:-
Answer: Option D. -> pinch-off and breakdown
Question 4. A JFET has high input impedance because ___________
it is made of semiconductor material
input is reverse biased
of impurity atoms
none of the above
Explanation:-
Answer: Option B. -> input is reverse biased
Question 5. A MOSFET differs from a JFET mainly because ___________
of power rating
the MOSFET has two gates
the JFET has a pn junction
none of the above
Explanation:-
Answer: Option C. -> the JFET has a pn junction
Question 6. If the reverse bias on the gate of a JFET is increased, then width of the conducting channel ___________
is decreased
is increased
remains the same
none of the above
Explanation:-
Answer: Option A. -> is decreased
Question 7. If the gate of a JFET is made less negative, the width of the conducting channel ___________
remains the same
is decreased
is increased
none of the above
Explanation:-
Answer: Option C. -> is increased
Question 8. If the cross-sectional area of the channel in n-channel JEFT increases, the drain current ___________
is increased
is decreased
remains the same
none of the above
Explanation:-
Answer: Option A. -> is increased
Question 9. 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 ___________
1
11.4
8.75
3.2
Explanation:-
Answer: Option B. -> 11.4
Question 10. In a certain CS JFET amplifier, RD= 1kΩ , RS= 560Ω , VDD=10V and gm= 4500 µS. If the source resistor is completely bypassed, the voltage gain is ___________