If the force exerted by an electric dipole on a charge q at a distance of 1 m is F, the force at a point 2 m away in the same direction will be

Question

If the force exerted by an electric dipole on a charge q at a distance of 1 m is F, the force at a point 2 m away in the same direction will be (A) (F/2) (B) (F/4) (C) (F/6) (D) (F/8)

Tardigrade Admin · Accepted Answer

Force exerted by an electric dipole on a charge is inversely proportional to the cube of distance of the charge from the centre of the dipole

F \propto \frac{1}{r ^{3}}

∴ \frac{F}{F ^{^{'}}} = (\frac{r ^{^{'}}}{r})^{3}

\frac{F}{F ^{^{'}}} = (\frac{2}{1})^{3}

F^{^{'}} = \frac{F}{8}

Q. If the force exerted by an electric dipole on a charge $q$ at a distance of $1 m$ is $F$ , the force at a point $2$ m away in the same direction will be

$\frac{F}{2}$

$\frac{F}{4}$

$\frac{F}{6}$

$\frac{F}{8}$

Force exerted by an electric dipole on a charge is inversely proportional to the cube of distance of the charge from the centre of the dipole
$F \propto \frac{1}{r ^{3}}$
$∴ \frac{F}{F ^{^{'}}} = (\frac{r ^{^{'}}}{r})^{3}$
$\frac{F}{F ^{^{'}}} = (\frac{2}{1})^{3}$
$F^{^{'}} = \frac{F}{8}$

Q. If the force exerted by an electric dipole on a charge q at a distance of 1m is F, the force at a point 2 m away in the same direction will be

2F​

4F​

6F​

8F​