Question

ABC is an equilateral triangle of side 1. M. D is the midpoint of BC. Charges of 4C, 4C and 3C are placed at B, C and D respectively. Find the resultant electric intensity at A.

• A. $2\times {10}^{9}N{C}^{-1}$
• B. $24\times {10}^{9}N{C}^{-1}$
• C. $48\times {10}^{9}N{C}^{-1}$
• D. $36\times {10}^{9}N{C}^{-1}$

Answer 1

The correct option is D $36\times {10}^{9}N{C}^{-1}$

$\therefore E_A=\frac{9\times {10}^9\times 3}{\left(\frac{3}{4}\right)}=36\times {10}^{9}N{C}^{-1}$