Question

Define dielectric constant of a medium in terms of the force between two electric charges.

Answer 1

Answer:

dielectric constant= force in free space / force in medium

Answer 2

Dielectric Constant of a medium is defined as the ratio of force experienced by the charges in free space to the force experienced by the charges in that medium.

In other words , di-electric constant is a measure of the ability of a medium to insulate nearby charges .

Mathematical Proof :

Let force experienced in free space be denoted as $F_{f}$ and the force experienced in the medium be $F_{m}$

Let dielectric constant be k ;

$F_{f} = \dfrac{1}{4\pi\epsilon_{0}} \bigg \{\dfrac{(q1)(q2)}{ {d}^{2} } \bigg \} \: \: \: \: \: ....(1)$

$F_{m} = \dfrac{1}{4\pi\epsilon_{0}k} \bigg \{\dfrac{(q1)(q2)}{ {d}^{2} } \bigg \} \: \: \: \: \: ....(2)$

Dividing the two equations , we get :

$\therefore \dfrac{F_{f}}{F_{m}} = k$

[Hence Proved]