A charged particle of mass `m` and charge `q` travels on a circular path of radius `r` that is perpendicular to a magnetic field `B`. The time takeen by the particle to complete one revolution is

Options

A. `(2pimq)/B`
B. `(2piq^(2))/B`
C. `(2piq^(2)B)/m`
D. `(2pim)/(qB)`

Answer

4

Explanation

Magnetic force `F=qupsilonB` …(i)
Centripetal force
`F=(mepsilon^(2))/r`...(ii)
From Eq. (i) and
`(mepsilon^(2))/r=qepsilonB rArrr=(mepsilon)/(qB)`
The time taken by the particle to complete one revolution.
`T=(2pir)/v=(2pimv)/(qB)=(2pim)/(qB)`