Question

When air is replaced by a dielectric medium of constant k, the maximum force of attraction between two charges separated by a distance

• A. Decreases k times
• B. Remains unchanged
• C. Increases k times
• D. Increases $k^{-1}$ times

Answer 1

The correct option is A Decreases k times

$F^{\prime }=\frac{1}{4\pi {\epsilon }_0}\frac{q_1{q}_2}{r^2}=\frac{F}{K}$
If F is the force in air, then F' is less than F since $K>1$ .