1. In an analog signal, the information is represented by:
A. Discrete values
B. Digital pulses
C. Continuous values
D. Binary data
Answer: C. Continuous values
2. Which of the following is the unit of current?
A. Volt
B. Ampere
C. Ohm
D. Watt
Answer: B. Ampere
3. The ideal voltage gain of an operational amplifier (op-amp) in an open-loop configuration is:
A. Zero
B. Infinite
C. 1
D. 10
Answer: B. Infinite
4. In an ideal operational amplifier, the input impedance is:
A. Zero
B. High
C. Low
D. Variable
Answer: B. High
5. The output of an inverting amplifier with a gain of 5 and an input signal of 2V will be:
A. 2V
B. -2V
C. 10V
D. -10V
Answer: D. -10V
6. The working of a transistor is based on the principle of:
A. Amplification
B. Switching
C. Rectification
D. Induction
Answer: A. Amplification
7. The current amplification factor of a transistor is also known as:
A. Beta (β)
B. Alpha (α)
C. Gain
D. Voltage gain
Answer: A. Beta (β)
8. In a common-emitter amplifier configuration, the input is applied to the:
A. Base
B. Collector
C. Emitter
D. Load
Answer: A. Base
9. The function of a coupling capacitor in an amplifier circuit is to:
A. Block DC and allow AC to pass
B. Block both AC and DC
C. Amplify the signal
D. Stabilize the current
Answer: A. Block DC and allow AC to pass
10. In a transistor, the region of operation where both the base-emitter and collector-base junctions are forward-biased is called:
A. Cut-off region
B. Active region
C. Saturation region
D. Reverse bias region
Answer: B. Active region
11. An ideal operational amplifier has:
A. Infinite input impedance and zero output impedance
B. Zero input impedance and infinite output impedance
C. Finite input impedance and finite output impedance
D. No input impedance and no output impedance
Answer: A. Infinite input impedance and zero output impedance
12. A differential amplifier amplifies the difference between:
A. Two input voltages
B. Two output currents
C. The input and ground voltage
D. A signal and the power supply voltage
Answer: A. Two input voltages
13. The gain of a non-inverting amplifier is given by the formula:
A. 1+RfR11 + \frac{R_f}{R_1}
B. RfR1\frac{R_f}{R_1}
C. 1−RfR11 – \frac{R_f}{R_1}
D. R1Rf\frac{R_1}{R_f}
Answer: A. 1+RfR11 + \frac{R_f}{R_1}
14. The primary characteristic of an ideal op-amp is:
A. High input impedance and low output impedance
B. Low input impedance and high output impedance
C. Low input impedance and high output impedance
D. High input impedance and high output impedance
Answer: A. High input impedance and low output impedance
15. A voltage follower (buffer) amplifier has a gain of:
A. 0
B. 1
C. 10
D. -1
Answer: B. 1
16. A diode allows current to flow:
A. In both directions
B. In one direction only
C. Only when forward biased
D. Only when reverse biased
Answer: B. In one direction only
17. A half-wave rectifier:
A. Allows both half-cycles of the input AC signal to pass
B. Only allows the positive half-cycle of the AC signal to pass
C. Only allows the negative half-cycle of the AC signal to pass
D. Works only with DC signals
Answer: B. Only allows the positive half-cycle of the AC signal to pass
18. A full-wave rectifier uses:
A. One diode
B. Two diodes
C. Four diodes
D. No diodes
Answer: C. Four diodes
19. A Zener diode is used primarily for:
A. Rectification
B. Amplification
C. Voltage regulation
D. Signal modulation
Answer: C. Voltage regulation
20. The efficiency of a half-wave rectifier is approximately:
A. 40.6%
B. 50%
C. 60%
D. 80%
Answer: A. 40.6%
21. A low-pass filter allows:
A. Low frequencies to pass and blocks high frequencies
B. High frequencies to pass and blocks low frequencies
C. Both high and low frequencies to pass equally
D. Only DC signals to pass
Answer: A. Low frequencies to pass and blocks high frequencies
22. The primary function of a band-pass filter is to:
A. Pass all frequencies
B. Block all frequencies
C. Pass a specific range of frequencies
D. Pass only high-frequency signals
Answer: C. Pass a specific range of frequencies
23. An oscillator generates a:
A. DC signal
B. High-frequency signal
C. Low-frequency signal
D. Constant voltage
Answer: B. High-frequency signal
24. A common application of a Colpitts oscillator is in:
A. Radio frequency (RF) generation
B. Power supply regulation
C. Low-frequency amplification
D. Digital signal processing
Answer: A. Radio frequency (RF) generation
25. A crystal oscillator is known for its:
A. Low frequency
B. High precision and stability
C. Low power consumption
D. High efficiency
Answer: B. High precision and stability