To derive an expression for electrostatic potential due to a point charge.
Suppose we have to calculate electrostatic potential at any point P due to a single point charge +q at O; where OP = r.
The electrostatic force on unit positive charge at A, when brought from infinity is :
F = \(\frac{q}{4\pi ∈_0.x^2}\)
In moving a unit positive charge from A to B,
Work done,
dw = \(\vec F.\vec{dx}\)
= F dx cos 180˚
= -F dx
∴ Total work done in moving unit positive charge form ∞ to the point p is :
By definition, the electrostatic potential at P due to charge q :
