1. Electric Charges and Fields
medium

An electron is moving round the nucleus of a hydrogen atom in a circular orbit of radius $r$. The coulomb force $\overrightarrow F $ between the two is (Where $K = \frac{1}{{4\pi {\varepsilon _0}}}$)

A

$ - K\frac{{{e^2}}}{{{r^3}}}\hat r$

B

$K\frac{{{e^2}}}{{{r^3}}}\vec r$

C

$ - K\frac{{{e^2}}}{{{r^3}}}\vec r$

D

$K\frac{{{e^2}}}{{{r^2}}}\hat r$

(AIPMT-2003)

Solution

$\overrightarrow {F\,} = – \,k\frac{{{e^2}}}{{{r^2}}}\hat r = – \,k.\frac{{{e^2}}}{{{r^3}}}\overrightarrow {r\,} $           $\left( {\,\,\hat r = \frac{{\overrightarrow {r\,} }}{r}} \right)$

Standard 12
Physics

Similar Questions

Start a Free Trial Now

Confusing about what to choose? Our team will schedule a demo shortly.