A particle of charge $q$ and mass $m$ is moving with a velocity $-v \hat{ i }(v \neq 0)$ towards a large screen placed in the $Y - Z$ plane at a distance $d.$ If there is a magnetic field $\overrightarrow{ B }= B _{0} \hat{ k },$ the minimum value of $v$ for which the particle will not hit the screen is
JEE MAIN 2020, Medium
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In uniform magnetic field particle moves in a circular path, if the radius of the circular path is $'d',$ particle will not hit the screen.

$d =\frac{ mv }{ qB _{0}}$

$v =\frac{ q B _{0} d }{ m }$

$\therefore$ correct option is $(2)$

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