Question

The uniform electric field in a region surrounding the origin is along the $x-$axis. A small circle is drawn with the center at the origin cutting the axes at points $\text{A, B, C}$ and $\text{D}$ having coordinates $(a,0),(0,a),(-a,0)$ and $(0,-a)$ respectively, as shown in figure. Find the point at which the potential is minimum.

• A. $\text{A}$
• B. $\text{B}$
• C. $\text{C}$
• D. $\text{D}$

Answer 1

The correct option is A $\text{A}$

We know that, electric field will be directed from positive charge to negative charge.

$\therefore$ Potential decreases along the direction of electric field.

From the figure, we can conclude that,

$\text{C}$ is at high potential, as it is the left most point relative to other points on the circle.

$\text{B}$ and $\text{D}$ are at the same potential, as they both are along the perpendicular to the electric field.

$\text{A}$ is at low potential, as it is the right most point relative to other points on the circle.

Hence, option (a) is the correct answer.