A collimated beam of charged and uncharged particles is directed towards a hole marked $P$ on a screen as shown below. If the electric and magnetic fields as indicated below are turned $ON$
KVPY 2020, Medium
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$(c)$ The force on a charged particle moving in combined electric and magnetic field is
$F =q( E + v \times B )$
For given direction of $v$, the net force is in downward direction. So, no charge will be able to go through the hole $P$.
Hence, only neutral particle will go undeviated.
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