Electronic Devices MCQ Questions and Answers for Practice

1. A transistor has how many PN Junctions?

1. 1
2. 2
3. 3
4. 4

2. In an npn transistor, the majority carriers in the emitter are neither both free electrons

1. free electrons
2. holes
3. niether (a) and (b)
4. both (a) and (b)

3. The barrier potential across each silicon depletion layer is

1. 0 V
2. 0.3 V
3. 0.7 V
4. 1 V

4. The base of an npn transistor is thin and

1. Heavily doped
2. Lightly doped
3. Metallic
4. Doped by a Pentavalent material

5. The emitter of a transistor is generally doped the heaviest because it

1. has to supply the charge carriers
2. is the first region of the transistor
3. must possess low resistance
4. has to dissipate maximum power

6. When a transistor is fully switched ON, it is said to be

1. shorted
2. saturated
3. open
4. cut-off

7. A FET consists of a

1. source
2. drain
3. gate
4. all the above

8. The extremely high input impedance of a MOSFET is primarily due to the

1. absence of its channel
2. negative gate-source voltage
3. depletion of current carriers
4. extremely small leakage current of its gate capacitor

9. When a transistor is used as a switch, it is stable in which two distinct regions?

1. saturation and active
2. active and cutoff
3. saturation and cutoff
4. none of the above

10. The term BJT is short for

1. binary junction transistor
2. both junction transistor
3. base junction transistor
4. bipolar junction transistor

11. What are the two types of bipolar junction transistors?

1. pnn and nnp
2. ppn and nnp
3. pts and stp
4. npn and pnp

12. 12. The magnitude of dark current in a photo-transistor usually falls in what range?

1. mA
2. nA
3. MA
4. pA

13. Junction Field Effect Transistors (JFET) contain how many diodes?

1. 4
2. 3
3. 2
4. 1

14. When not in use, MOSFET pins are kept at the same potential through the use of:

1. conductive foam
2. nonconductive foam
3. shipping foil
4. a wrist strap

15. A MOSFET has how many terminals?

1. 2 or 3
2. 3
3. 4
4. 3 or 4