A point charge of magnitude $+ 4, μ C$ is placed at the origin. Calculate the electric potential at a point $P$ located $10, cm$ from the charge. Take the potential to be zero at infinity. Use $k = 9 \times 1 0^{9}, N m^{2} C^{- 2}$ .

easy 1 mark Class 12 · Physics · Electrostatic Potential and Capacitance

Answer

3.6 \times 1 0^{5}, V

The correct answer is $3.6 \times 1 0^{5}, V$ — Simplify the expression. $V = 3.6 \times 1 0^{5}, V$

Step-by-step solution

Determine the distance $r$ from the charge to point $P$ . $r = 10, cm = 0.10, m$
Write the formula for electric potential due to a point charge. $V = \frac{k q}{r}$
Insert the given values. $V = \frac{9 \times 1 0 ^{9} \times 4 \times 1 0 ^{- 6}}{0.10}$
Simplify the expression. $V = 3.6 \times 1 0^{5}, V$

Common mistake: Using the wrong unit for distance (cm instead of m)

Concept tested: Electric potential of a point charge

Published 14 September 2026 · Last updated 16 September 2026 · How this solution was prepared and checked