OnlineCBT
Physics · Electrostatic Potential
हिन्दीA point charge \( Q \) is located at the origin. The work done by an external agent in slowly moving a test charge \( q \) from point \( r_1 \) to \( r_2 \) along a radial line (\( r_2 > r_1 \)) is proportional to:
Correct answer · Option 4
\( (\frac{1}{r_1} - \frac{1}{r_2}) \)
Explanation
Work done \( W = -\int_{r_1}^{r_2} \frac{Qq}{4\pi\varepsilon_0 r^2} dr = \frac{Qq}{4\pi\varepsilon_0} (\frac{1}{r_1} - \frac{1}{r_2}) \).
