Consider the situation of the previous problem. A particle having charge q and mass m is projected from the point Q in a direction going into the plane of the diagram. It is found to describe a circle of radius r between the two plates. Find the speed of the charged particle.

Explanation

Given charge =q
and mass= m radiu = r
We know that,
Radius descirbed by a charged particle in
a magnetic field
`r=(mv)/(qB)`
`rArr v = (Bqr)/(m) = (mu_okqr)/(m)`
[using Ampere's circuital law]