An electron is shot at an initial speed of V0 m/s, at an angle theta from the x-axis. It moves through a uniform electric field E j^ . A screen for detecting electrons is positioned parallel to the y-axis , ata a distance x'. What is the velocity of the electron when it hits the screen.?

hi,

x component of velocity = V0 cos θ

accleration in x direction is zer0

x component of velocity after tsec , v1x =  V0 cos θ , 

& time taken to reach the sc reen ,t =  x'/ V0 cos θ

vertical component of velocity = V0 sin θ  & accl. = -eE /m

    vertical velocity at time  t  ,  v1y  =   V0 sin θ  -  eE /m  * x'/ V0 cos θ

                                                    =   V0 sin θ  -  eE  x'/ mV0 cos θ 

velocity after time t ,v1  = √ v1x^2  + v1y ^2

                                   =  √   {  V0 cos θ)^2  + ( V0 sin θ  -  eE  x'/ mV0 cos θ  )^2 }