Question

The electric force acting between two point charges kept at a certain distance in vacuum is 16 N. If the same two charges are kept at the same distance in a medium of dielectric constant 8, the electric force acting between them is ____________ N.

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Answer 1

The electric force acting between two point charges kept at a certain distance in vacuum is 16 N. If the same two charges are kept at the same distance in a medium of dielectric constant 8, the electric force acting between them is 2 N.

Explanation:

Electric force acting between the two charges is,

${\displaystyle \text{F}=\frac{1}{4\pi {\epsilon }_0\text{K}}\times \frac{{\text{q}}_1{\text{q}}_2}{{\text{r}}^2}\Rightarrow \text{F'}=\frac{\text{F}}{\text{K}}}$

${\displaystyle \therefore \text{Net force on each charge}=\frac{16}{8}=2\text{N}}$