Two equal positive charges are kept at points A and B. The electric potential at the points between A and B (excluding these points) is studied while moving from A to B. The potential
Potential due to a point charge at a distance r is given by:
Therefore, at a point very nearby to A and B, r → 0 ∴ V → ∞
i.e.
At a very nearby point right to A and a very nearby point left to B, potential will tend to ∞ (maximum possible value) as separation will tend to zero. That means at a point somewhere in the middle of path AB, the potential will acquire its minimum value.
Therefore, while moving from A to B, potential will first decrease and then increase.