What is CONTINOUS CHARGE DISTRIBUTION, class 12th, Physics

We can consider small area element ∆s on the surface of the conduct. This area element is very small on the macroscopic scale, but big enough to include a very large number of electrons. If ∆q is the amount of charge on this element, we define surface charge density [ ] at the area element by

                                = ∆q / ∆s

We can repeat the process at different points on surface of the conductor and thus arrive at a continuous function , called the surface charge density. at the microscopic level, charge distribution is discontinuos.

When charge is distributed along a line, straight or curved, we define linear charge density

                               = ∆q / ∆l

where ∆l is a small line element of wire on the macroscopic scale that includes a large number of microscopic charged constituents and ∆q is the charge contained in that line element.

The volume charge density is defined in a similar manner as

                             ρ = ∆q / ∆v            

Where ∆q is the charge included in the macroscopically small volume element ∆v that include a large number of microscopic charged constituents. The units of ρ are c/m3.