The electric field at the origin is along the positive x-axis. A small circle is drawn with the center at the origin cutting the axes at points A, B, C and D having coordinates (α, 0), (0, α), (–α, 0), (0, –α) respectively. Out of the points on the periphery of the circle, the potential is minimum at

The electric field at the origin is along the positive x-axis. A small circle is drawn with the center at the origin cutting the axes at points A, B, C and D having coordinates (α, 0), (0, α), (–α, 0), (0, –α) respectively. Out of the points on the periphery of the circle, the potential is minimum at

As the electric field is in +X direction, that is field lines will flow from point C to point A. And as we already know that field lines flow from high potential to low potential, that means point A needs to be at a low potential region and point C needs to be at a high potential region.

Points B and D are equipotential.

The order of potentials is:

V_C > V_B =V_D > V_A

Therefore, potential is minimum at A.

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