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Question
Consider the situation of the previous problem. A particle having charge q and mass mis 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.
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Solution
Given:
Charge = q
Mass = m
Radius = r
We know that the radius described by a charged particle in a magnetic field is given by
`r = (mv) /(qB)`
Using Ampere circuital law
`int B .dl = mu_0i`
`⇒ B. dl = mu _0 kdl `
`⇒ B = mu_0 k`
`⇒ v =(Bqr)/m = (mu_0kqr)/m`
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