Q. A long cylindrical volume contains a uniformly distributed charge of density $\rho$. The radius of cylindrical volume is $R$. A charge particle $(q)$ revolves around the cylinder in a circular path. The kinetic of the particle is :
Solution:
$E =2 \pi r \ell=\frac{\rho \pi r ^{2} \ell}{\varepsilon_{0}}$
$qE =\frac{ q \rho R ^{2}}{2 \varepsilon_{0} r }=\frac{ mv ^{2}}{ r }$
$mv ^{2}=\frac{ q \rho R ^{2}}{2 \varepsilon_{0}}$
