An electron moves in a circular orbit with a uniform speed v. It produces a magnetic field B at the centre of the circle. Prove that the radius of the circle is proportional to `sqrt(V/B)`.

Explanation

The magnetic field produce by moving electron in circular path.
`B=(mu_0i)/(2r) " " i=q/r `, q=e
`=(mu_0q)/(2rt) " " t=(2pir)/v`
`B=(mu_0qv)/(4pir^2) rArr r=sqrt((mu_0qv)/(4piB)) rArr r prop sqrt(v/B)`