**Electric Potential Definition:**

The Electric Potential point due to a charge is the work done in bringing a unit positive charge from infinity to that point. The concept of electric potential is extremely important for the determination of capacitance in a circuit since the latter is defined as the charge per unit potential. We shall now discuss in detail the Electric Potential Definition due to some important conductor arrangements.

**1.Potential at a Charged Single Conductor:**

Consider a long straight cylindrical conductor A of radius r metres. Let the conductor operate at such a potential (V_{A}) that charge Q_{A} coulombs per metre exists on the conductor. It is desired to find the expression for V_{A}. The electric intensity E at a distance x from the centre of the conductor in air is given by:

As x approaches infinity, the value of E approaches zero. Therefore, the potential difference between conductor A and infinity distant neutral plane is given by :

**2.Potential at a Conductor in a Group of Charged Conductors:**

Consider a group of long straight conductors A, B, C etc. operating at potentials such that charges Q_{A}, Q_{B}, Q_{c} etc. coulomb per metre length exist on the respective conductors (see Fig. 9.20). Let us find the potential at A (i.e. V_{A}) in this arrangement. Potential at A due to, its own charge (i.e. Q_{A})

Potential at conductor A due to charge Q_{B}

Potential at conductor A due to charge Q_{c}.

Overall potential difference between conductor A and infinite neutral plane is