22.
On the basis of the type of chemical bonds, solids may be classified into

23.
Which of the following are true for relative dielectric constant?
1. It is dimensionless.
2. It is equal to 1 for vacuum.
3. It is equal to 1 for all substances.

24.
In an intrinsic semiconductor, at a given temperature T

25.
The resistance of a photoconductor