In this section of Electronic Devices and Circuits.It contain A.C Models – AC Analysis of BJT circuits and small signal amplifier MCQs (Multiple Choice Questions Answers).All the MCQs (Multiple Choice Question Answers) requires in depth reading of Electronic Devices and Circuits Subject as the hardness level of MCQs have been kept to advance level.These Sets of Questions are very helpful in Preparing for various Competitive Exams and University level Exams.
This Section Covers below lists of topics :
- Base-Biased Amplifier MCQs
- Emitter-Biased Amplifier MCQs
- Small Signal Operation MCQs
- AC Beta MCQs
- AC Resistance of the Emitter Diode MCQs
- Two Transistors Models MCQs
- Analyzing an Amplifier MCQs
- AC Quantities on the Data Sheet MCQs
Practice it now to sharpen your concept.
PRACTICE IT NOW TO SHARPEN YOUR CONCEPT AND KNOWLEDGE
1. For dc, the current in a coupling circuit is
- Zero
- Maximum
- Minimum
- Average
A. Zero
2. The current in a coupling circuit for high frequencies is
- Zero
- Maximum
- Minimum
- Average
B. Maximum
3. A coupling capacitor is
- A dc short
- An ac open
- A dc open and an ac short
- A dc short and an ac open
C. A dc open and an ac short
4. In a bypass circuit, the top of a capacitor is
- An open
- A short
- An ac ground
- A mechanical ground
C. An ac ground
5. The capacitor that produces an ac ground is called a
- Bypass capacitor
- Coupling capacitor
- Dc open
- Ac open
A. Bypass capacitor
6. The capacitors of a CE amplifier appear
- Open to ac
- Shorted to dc
- Open to supply voltage
- Shorted to ac
D. Shorted to ac
7. Reducing all dc sources to zero is one of the steps in getting the
- DC equivalent circuit
- AC equivalent circuit
- Complete amplifier circuit
- Voltage-divider biased circuit
B. AC equivalent circuit
8. The ac equivalent circuit is derived from the original circuit by shorting all
- Resistors
- Capacitors
- Inductors
- Transistors
B. Capacitors
9. When the ac base voltage is too large, the ac emitter current is
- Sinusoidal
- Constant
- Distorted
- Alternating
C. Distorted
10. In a CE amplifier with a large input signal, the positive half cycle of the ac emitter current is
- Equal to the negative half cycle
- Smaller than the negative half cycle
- Larger than the negative half cycle
- Equal to the negative half cycle
C. Larger than the negative half cycle
11. Ac emitter resistance equals 25 mV divided by the
- Quiescent base current
- DC emitter current
- AC emitter current
- Change in collector current
B. DC emitter current
12. To reduce the distortion in a CE amplifier, reduce the
- DC emitter current
- Base-emitter voltage
- Collector current
- AC base voltage
D. AC base voltage
13. If the ac voltage across the emitter diode is 1 mV and the ac emitter current is 0.1 mA, the ac resistance of the emitter diode is
- 1 ohm
- 10 ohm
- 100 ohm
- 1 kohm
B. 10 ohm
14. A graph of ac emitter current versus ac base-emitter voltage applies to the
- Transistor
- Emitter diode
- Collector diode
- Power supply
B. Emitter diode
15. The output voltage of a CE amplifier is
- Amplified
- Inverted
- 180 degrees out of phase with the input
- All of the above
D. All of the above
16. The emitter of a CE amplifier has no ac voltage because of the
- DC voltage on it
- Bypass capacitor
- Coupling capacitor
- Load resistor
B. Bypass capacitor
17. The voltage across the load resistor of a CE amplifier is
- Dc and ac
- DC only
- AC only
- Neither dc nor ac
C. AC only
18. The ac collector current is approximately equal to the
- AC base current
- AC emitter current
- AC source current
- AC bypass current
B. AC emitter current
19. The ac emitter current times the ac emitter resistance equals the
- Dc emitter voltage
- AC base voltage
- AC collector voltage
- Supply voltage
B. AC base voltage
20. The ac collector current equals the ac base current times the
- AC collector resistance
- DC current gain
- AC current gain
- Generator voltage
C. AC current gain
21. The emitter is at ac ground in a
- CB stage
- CC stage
- CE stage
- None of these
C. CE stage
22. The output voltage of a CE stage is usually
- Constant
- Dependent on re’
- Small
- Less the one
B. Dependent on re’
23. The voltage gain equals the output voltage divided by the
- Input voltage
- AC emitter resistance
- AC collector resistance
- Generator voltage
A. Input voltage
24. The input impedance of the base increases when
- Beta increases
- Supply voltage increases
- Beta decreases
- AC collector resistance increases
A. Beta increases
25. Voltage gain is directly proportional to
- Beta
- Ac emitter resistance
- DC collector voltage
- AC collector resistance
D. AC collector resistance
26. Compared to the ac resistance of the emitter diode, the feedback resistance of a swamped amplifier should be
- Small
- Equal
- Large
- Zero
C. Large
27. Compared to a CE stage, a swamped amplifier has an input impedance that is
- Smaller
- Equal
- Larger
- Zero
C. Larger
28. To reduce the distortion of an amplified signal, you can increase the
- Collector resistance
- Emitter feedback resistance
- Generator resistance
- Load resistance
B. Emitter feedback resistance
29. The emitter of a swamped amplifier
- Is grounded
- Has no de voltage
- Has an ac voltage
- Has no ac voltage
C. Has an ac voltage
30. A swamped amplifier uses
- Base bias
- Positive feedback
- Negative feedback
- A grounded emitter
C. Negative feedback
31. In a swamped amplifier, the effects of the emitter diode become
- Important to voltage gain
- Critical to input impedance
- Significant to the analysis
- Unimportant
D. Unimportant
32. The feedback resistor
- Increases voltage gain
- Reduces distortion
- Decreases collector resistance
- Decreases input impedance
B. Reduces distortion
33. The feedback resistor
- Stabilizes voltage gain
- Increases distortion
- Increases collector resistance
- Decreases input impedance
A. Stabilizes voltage gain
34. The ac collector resistance of the first stage includes the
- Load resistance
- Input impedance of first stage
- Emitter resistance of first stage
- Input impedance of second stage
D. Input impedance of second stage
35. If the emitter bypass capacitor opens, the ac output voltage will
- Decrease
- Increase
- Remain the same
- Equal zero
A. Decrease
36. If the collector resistor is shorted, the ac output voltage will
- Decrease
- Increase
- Remain the same
- Equal zero
D. Equal zero
37. If the load resistance is open, the ac output voltage will
- Decrease
- Increase
- Remain the same
- Equal zero
B. Increase
38. If any capacitor is open, the ac output voltage will
- Decrease
- Increase
- Remain the same
- Equal zero
A. Decrease
39. If the input coupling capacitor is open, the ac input voltage will
- Decrease
- Increase
- Remain the same
- Equal zero
D. Equal zero
40. If the bypass capacitor is open, the ac input voltage will
- Decrease
- Increase
- Remain the same
- Equal zero
B. Increase
41. If the output coupling capacitor is open, the ac input voltage will
- Decrease
- Increase
- Remain the same
- Equal zero
C. Remain the same
42. If the emitter resistor is open, the ac input voltage will
- Decrease
- Increase
- Remain the same
- Equal zero
B. Increase
43. If the collector resistor is open, the ac input voltage will
- Decrease
- Increase
- Remain the same
- Equal approximately zero
A. Decrease
44. If the emitter bypass capacitor is shorted, the ac input voltage will
- Decrease
- Increase
- Remain the same
- Equal zero
A. Decrease
