Consider the situation of the previous problem. Consider the fastest electron emitted parallel to the large metal plate. Find the displacement of this electron parallel to its initial velocity before it strikes the large metal plate.
electric field 
Acceleration of charged particle is given by,
Where q is the charge on electron
E is the electric field
m is the mass of electron
∴ 
To calculate time, we know that 
∴ 
.
From Q: 31 the value of kinetic energy =1.2eV [from eq (1)]
∴ K.E. =
J
We also know that 
∴ 
∴ Displacement, S=v× t
1