Electronic Devices and Circuit Theory- Bipolar Junction Transistors Questions and Answers
The Bipolar Junction Transistor (BJT) is a core topic in electronic devices and circuit theory, frequently seen in aptitude questions and answers with explanations for GATE, ESE, and DRDO exams. BJTs function as amplifiers and switches, and their behavior is determined by input–output current relations. Understanding concepts like current gain (β), biasing, and load line analysis is crucial for solving numerical and circuit-based aptitude problems. Practicing electronics aptitude questions with solutions PDF helps students strengthen fundamentals and excel in technical assessments.
Electronic Devices and Circuit Theory- Bipolar Junction Transistors
Showing 10 of
19 questions
1. A transistor amplifier has a voltage gain of 100. If the input voltage is 75 mV, the output voltage is:
- 1.33 V
- 7.5 V
- 13.3 V
- 15 V
2. For normal operation of a pnp BJT, the base must be ________ with respect to the emitter and ________ with respect to the collector.
- positive, negative
- positive, positive
- negative, positive
- negative, negative
3. When a transistor is used as a switch, it is stable in which two distinct regions?
- saturation and active
- active and cutoff
- saturation and cutoff
- none of the above
4. The term BJT is short for
- base junction transistor.
- binary junction transistor.
- both junction transistor.
- bipolar junction transistor.
5. For a silicon transistor, when a base-emitter junction is forward-biased, it has a nominal voltage drop of
- 0.7 V.
- 0.3 V.
- 0.2 V.
- VCC.
6. Refer to Figure 4-3. The measured voltage, VCE, is 20 V. The transistor is in
- saturation.
- cutoff.
- normal.
- not enough data.
7. What are the two types of bipolar junction transistors?
- npn and pnp
- pnn and nnp
- ppn and nnp
- pts and stp
8. What is the order of doping, from heavily to lightly doped, for each region?
- base, collector, emitter
- emitter, collector, base
- emitter, base, collector
- collector, emitter, base
9. The magnitude of dark current in a phototransistor usually falls in what range?
- mA
- µA
- nA
- pA
10. Refer to Figure 4-3. You measure VCE and find it nearly equal to zero. You now know that the transistor is
- operating in cutoff.
- operating normally.
- operating in saturation.
- operating below cutoff.