A particle of mass m and charge -q enters the region between the two charged plates initially moving along x-axis with speed `v_(x)` as shown in figure. The length of plate is L and a uniform electric field E is maintained between the plates. The vertical deflection of the particle at the far edge of the plate is

Explanation

Here charged particle experiences force along vertical direction which is equal to Eq.
As a result its acceleration in the vertical direction is `(Eq)/(m)`.
Along the horizontal direction, its velocity doesnot change.
Time taken by the charge to reach the other end of the plate is `t=(L)/(U)`
During this time its vertical deflection is given by `y=(1)/(2) at^(2)`
`y=(1)/(2) (Eq)/(m)((L)/(U))^(2) =(EqL^(2))/(2mU^(2))`