1. Feedback in an electronic system refers to:
A. The process of supplying energy to the system
B. The process of feeding the output signal back into the input
C. The resistance in the input circuit
D. The voltage gain of the amplifier
Answer: B. The process of feeding the output signal back into the input
2. The main purpose of feedback in an amplifier is to:
A. Increase the output power
B. Stabilize the gain and improve performance
C. Reduce the input impedance
D. Increase the distortion in the output signal
Answer: B. Stabilize the gain and improve performance
3. Feedback that increases the input signal and leads to an increase in output signal is called:
A. Negative feedback
B. Positive feedback
C. Distortion feedback
D. Linear feedback
Answer: B. Positive feedback
4. Negative feedback in an amplifier results in:
A. Increased gain
B. Decreased distortion and improved stability
C. Decreased bandwidth
D. Increased distortion
Answer: B. Decreased distortion and improved stability
5. In a system with negative feedback, the feedback signal is:
A. In phase with the input signal
B. In phase with the output signal
C. Out of phase with the input signal
D. Unrelated to the input signal
Answer: C. Out of phase with the input signal
6. In which type of feedback is the feedback signal directly added to the input signal?
A. Positive feedback
B. Negative feedback
C. Unidirectional feedback
D. Nonlinear feedback
Answer: A. Positive feedback
7. The effect of positive feedback in a system is generally to:
A. Improve stability
B. Decrease the frequency response
C. Make the system unstable or oscillate
D. Increase the power consumption
Answer: C. Make the system unstable or oscillate
8. Which of the following is a common application of negative feedback in amplifiers?
A. To increase the overall gain of the amplifier
B. To improve the linearity and bandwidth of the amplifier
C. To make the amplifier oscillate
D. To increase the distortion in the output
Answer: B. To improve the linearity and bandwidth of the amplifier
9. In a feedback amplifier, if the feedback resistor is connected from the output to the inverting input, the feedback is said to be:
A. Positive
B. Negative
C. Direct
D. Sinusoidal
Answer: B. Negative
10. Which of the following is a primary advantage of negative feedback in amplifiers?
A. Improved gain stability
B. Increased cost
C. Reduced linearity
D. Reduced bandwidth
Answer: A. Improved gain stability
11. In an operational amplifier, the use of negative feedback generally leads to:
A. High distortion and low bandwidth
B. Low distortion and high bandwidth
C. High gain with low input impedance
D. Low gain with high output impedance
Answer: B. Low distortion and high bandwidth
12. In a voltage amplifier with feedback, the overall voltage gain is determined by:
A. The amplifier’s open-loop gain and the feedback network
B. The feedback network alone
C. The power supply voltage
D. The input signal strength
Answer: A. The amplifier’s open-loop gain and the feedback network
13. In a positive feedback system, if the feedback is too high, the system will:
A. Stabilize
B. Oscillate
C. Become more linear
D. Decrease its gain
Answer: B. Oscillate
14. In an amplifier circuit with negative feedback, what effect does the feedback have on the input impedance?
A. It increases the input impedance
B. It decreases the input impedance
C. It has no effect on input impedance
D. It increases the output impedance
Answer: B. It decreases the input impedance
15. The feedback in an emitter follower amplifier is generally:
A. Positive feedback
B. Negative feedback
C. Neutral feedback
D. Frequency-dependent feedback
Answer: B. Negative feedback
16. Which of the following is an advantage of negative feedback in amplifiers?
A. Increases the gain but makes the system unstable
B. Reduces the system’s linearity
C. Reduces sensitivity to component variations
D. Increases noise and distortion
Answer: C. Reduces sensitivity to component variations
17. One of the disadvantages of positive feedback is that it can lead to:
A. Reduced noise
B. Greater gain stability
C. Oscillations or instability
D. Improved bandwidth
Answer: C. Oscillations or instability
18. Which type of feedback is typically used in a phase-locked loop (PLL) to maintain frequency synchronization?
A. Positive feedback
B. Negative feedback
C. None of the above
D. Both positive and negative feedback
Answer: B. Negative feedback
19. Which of the following is NOT an effect of negative feedback?
A. Improved stability
B. Reduced distortion
C. Increased power efficiency
D. Reduced bandwidth
Answer: D. Reduced bandwidth
20. The feedback used in a voltage regulator circuit is typically:
A. Positive feedback
B. Negative feedback
C. Zero feedback
D. Both positive and negative feedback
Answer: B. Negative feedback