Question

The electric field due to a point charge at a distance r depends according to inverse square law . State how the following quantities depend upon r.
(i) potential due to a point charge
(ii) potential at a distance r from the centre of a charged metallic sphere of radius R (r < R).​

Answer 1

The relation between potential and r can be given by the following formulas

• The potential due to a point charge is given by the formula

             V = q / 4πε₀r

        In this case the potential is inversely proprtional to r i.e, V∝ r⁻¹

• Potential at a distance r from the center of sphere of radius R is given by the formula

             V = q / 4πε₀R

       In this case the potential does not depends on r i.e, V∝ r⁰