Question

An electron of charge $e$ at rest is accelerated in a uniform electric field of strength $E$. The $KE$ attained by it as it travels through a distance $S$ is :

• A. $\frac{S}{Ee}$
• B. $EeS$
• C. $\frac{Ee}{S}$
• D. $\frac{Se}{E}$

Answer 1

Answer: (B)

$EeS$

Force on electron $=eE$

Acceleration $a=\frac{eE}{m}$

Initially it was at rest

$v^2=2as=\frac{2eES}{m}$

$KE=\frac{m{v}^2}{2}=eES$