Question

A charged particle of mass ‘m’ and charge ‘q’ is released from rest in an electric field of uniform strength E.
The kinetic energy of the particle after time ‘t’ is ___

• A. $\frac{2E^2{t}^2}{mg}$
• B. $\frac{E^{2}m{q}^2}{2t^2}$
• C. $\frac{E^2{q}^2{t}^2}{2m}$
• D. $\frac{Eqm}{2t}$

Answer 1

The correct option is C $\frac{E^2{q}^2{t}^2}{2m}$

$KE=\frac{1}{2}m[at{]}^2=\frac{1}{2}m{\left[\frac{Eq}{m}t\right]}^2$
$KE=\frac{E^2{q}^2{t}^2}{2m}$