whats charge density and its formula?

Question

anonymous · Answer

The charge carrier density denotes the number of charge carriers per volume it is measured in $$m ^{-1}$$ . as any density it can depend on position. it should not be confused with the charge density which is the number of charges per volum at a given energy. the carrier density is obtained by integrating the charge density over the energy that charges are allowed to have. the charge carrier density is aparticle density, so integrating it over volume V gives the number of charges carriers N in that volume.

the formula :
$$N = \int\limits_{v}^{} n (r) dV$$

where n(r) is the position depend on charge carrier density. if the density doesnt depend on position and is instead equal to constant  n0 this equation simplifies to $$N= V  \times n _{0}$$