EET 121 UPDATED ACTUAL QUESTIONS AND CORRECT ANSWERS

EET 121 UPDATED ACTUAL QUESTIONS AND CORRECT
ANSWERS

Question:
1. A certain transistor has a dc emitter current of 25 mA. The value of r'e is
Answer:
1 Ω.

Question:
2. A common-base amplifier has a high current gain
Answer:
False

Question:
3. A common-collector amplifier is also known as an emitter follower
Answer:
True

Question:
4. A common-emitter amplifier has very high input impedance, high voltage gain, and high current gain.
Answer:
False

Question:
5. A high input impedance amplifier could be implemented with a Darlington pair.
Answer:
True

Question:
6. For transistors
Answer:
the dc and ac current gains are usually different.

Question:
7. Refer to the figure above. If AV1 = 75 and AV2 = 95, AVT would be
Answer:
7125.

Question:
8. Refer to the figure above. If R2 opened, VCE would be
Answer:
0V

Question:
9. Refer to the figure above. If R2 opened, the value of IC would be

, Answer:
6.67 mA.

Question:
10. Refer to the figure above. If RC opened, VE would
Answer:
decrease

Question:
11. Refer to the figure above. If VB2 were higher than normal, the problem, if any, could be that
Answer:
C3 is shorted.

Question:
12. Refer to the figure above. If VE = 0, the trouble might be that
Answer:
R1 is open

Question:
13. Refer to the figure above. If an emitter-bypass capacitor were added, the voltage gain
Answer:
would increase

Question:
14. Refer to the figure above. If an emitter-bypass capacitor were installed, AV would be
Answer:
560.

Question:
15. Refer to the figure above. If the collector opened internally, the voltage on the collector would
Answer:
increase.

Question:
16. Refer to the figure above. If the emitter collector shorted, the voltage VC would be
Answer:
3.33 V.

Question:
17. Refer to the figure above. In servicing this amplifier Vout has a dc component in addition to the normal
ac output voltage. This would be caused by a(n)
Answer:
shorted C5

Question:
18. Refer to the figure above. The output signal at the collector of Q1 is higher than normal. This could be
caused by a(n)