Question

Charged beads are placed at the corners of a square in the various configuration as shown in figure. Black beads have charge -Q. Rank the configuration according to the magnitude of the electric field at the center of the square :

• A. $\left(a\right)>\left(e\right)>\left(c\right)>\left(b\right)>\left(d\right)$
• B. $\left(c\right)>\left(e\right)>\left(a\right)>\left(d\right)>\left(b\right)$
• C. $\left(a\right)=\left(c\right)>\left(e\right)>\left(b\right)>\left(d\right)$
• D. $\left(e\right)>\left(b\right)>\left(a\right)=\left(d\right)>\left(c\right)$

Answer 1

The correct option is D $\left(e\right)>\left(b\right)>\left(a\right)=\left(d\right)>\left(c\right)$

The final force direction is shown with the arrow and written as E. Fig (e) will have highest electric field in the center point. a) and d) will have same field due to the presence of opposite charge in the opposite corner. Fig c) will have zero field at center,