Q. Figure shows a triangular array of three point charges. The electric potential $V$ of these source charges at the midpoint $P$ of the base of the triangle is

$\left\lbrack \frac{1}{4\pi\epsilon_{0}} = 9 \times 10^{9}Nm^{2}C^{- 2} \right\rbrack$

A) $55\ kV$
B) 45 $kV$
C) 63 $kV$
D) 49 $kV$
Explanation

(b) $V_{P} = \frac{1}{4\pi\varepsilon_{0}}\left\lbrack \frac{q_{1}}{0.2} + \frac{q_{2}}{0.2} + \frac{q_{3}}{0.3} \right\rbrack$
$= 9 \times 10^{9}\left\lbrack \frac{1}{0.2} - \frac{2}{0.2} + \frac{3}{0.3} \right\rbrack \times 10^{- 6}$
$= 9 \times 10^{3}\lbrack 5 - 10 + 10\rbrack = 45 \times 10^{3} = 45kV$

Dr. Abubacker
Reviewed by Dr. Abubacker

Physics Educator & NEET/JEE Specialist

Ph.D. in Physics with 19+ years of teaching experience.