ELECTRONIC DEVICES QUESTION BANK FOR CLASS XII CBSE

1. Write one difference between crystalline solids and amorphous solids.
2. How does conductivity of a semiconductor change with temperature?
3. Why does the conductivity of a semiconductor increase with increase in temperature?
4. What is the order of energy gap in a semiconductor?
5. Give the ratio of the number of holes to the number of free electrons in an intrinsic semicounductor.
6. What is the net charge in a piece of p- type extrinsic semicounductor?
7. Name the charge carriers in an n - type semiconductor.
8. Draw energy band diagram for an n type semiconductor.
9. Draw energy band diagram for a p type semiconductor.
10. Define depletion region in an n - type semiconductor.
11. In which type of biasing of a diode is the resistance high?
12. Draw VI Characteristics of a diode in (a) Forward Bias (b) Reverse Bias
13. Distinguish between metals insulators and semiconductors on the basis of their energy bands.
14. What is an intrinsic semicounductor?
15. How is an intrinsic semiconductor converted into (a) N - type semiconductor (b) P- type semiconductor?
16. Explain the conduction in N -type and P - type semiconductor on the basis of bond theory and band theory
17. Distinguish between intrinsic and extrinsic semiconductors. Expalin why an N Type semiconductor is neutral though ne >> nh.
18. Explain briefly with a suitable circuit diagram how the VI characteristics of a diode is studied  when (i) Forward biased (ii) Reverse Biased.
19. How does the width of depletion region change when the diode is (a) forward biased (b) Reverse Biased?
20. Explain the functioning of diode as a (i) Half Wave rectifier (ii) Fullwave rectifier. Draw circuit diagrams and input and output wave forms.