Amplifiers with Negative Feedback Questions with Answers :-
1. When negative voltage feedback is applied to an amplifier, its voltage gain ……………….
- Is increased
- Is reduced
- Remains the same
- None of the above
Ansr : 2
2. The value of negative feedback fraction is always …………….
- Less than 1
- More than 1
- Equal to 1
- None of the above
Ansr : 1
3. If the output of an amplifier is 10 V and 100 mV from the output is fed back to the input, then feedback fraction is ………..
- 10
- 1
- 01
- 15
Ansr : 3
4. The gain of an amplifier without feedback is 100 db. If a negative feedback of 3 db is applied, the gain of the amplifier will become …………..
- 5 db
- 300 db
- 103 db
- 97 db
Ansr : 4
5. If the feedback fraction of an amplifier is 0.01, then voltage gain with negative feedback is approximately………..
- 500
- 100
- 1000
- 5000
Ansr : 2
6. A feedback circuit usually employs ……………… network
Resistive
Capacitive
Inductive
None of the above
Ansr : 1
7. The gain of an amplifier with feedback is known as ………….. gain
Resonant
Open loop
Closed loop
None of the above
Ansr : 3
8. When voltage feedback (negative) is applied to an amplifier, its input impedance ………….
Is decreased
Is increased
Remains the same
None of the above
Ansr : 2
9. When current feedback (negative) is applied to an amplifier, its input impedance …………..
Is decreased
Is increased
Remains the same
None of the above
Ansr : 1
10. Negative feedback is employed in ……………..
Oscillators
Rectifiers
Amplifiers
None of the above
Ansr : 3
11. Emitter follower is used for …………
Current gain
Impedance matching
Voltage gain
None of the above
Ansr : 2
12. The voltage gain of an emitter follower is ………..
Much less than 1
Approximately equal to 1
Greater than 1
None of the above
Ansr : 2
13. When current feedback (negative) is applied to an amplifier, its output impedance ……..
Is increased
Is decreased
Remains the same
None of the above
Ansr : 1
14. Emitter follower is a ……………….. circuit
Voltage feedback
Current feedback
Both voltage and current feedback
None of the above
Ansr : 1
15. If voltage feedback (negative) is applied to an amplifier, its output impedance …………..
Remains the same
Is increased
Is decreased
None of the above
Ansr : 3
16. When a negative voltage feedback is applied to an amplifier, its bandwidth……….
- Is increased
- Is decreased
- Remains the same
- Insufficient data
Ansr : 1
17. An emitter follower has ………… input impedance
- Zero
- Low
- High
- None of the above
Ansr : 3
19. The output impedance of an emitter follower is ……….
- High
- Very high
- Almost zero
- Low
Ansr : 4