Q. The path of a charge particle after it enters a region of a uniform electrostatic field with velocity perpendicular to the field will be
J & K CETJ & K CET 2015
Solution:
Consider a particle of charge $q$ and mass $m$ enters a region of uniform electric field $E$.
At any instant $t$, coordinates are
$x=\frac{1}{2} \times \frac{q E}{m} t^{2}$ ...(i)
and $y=u t$
From Eqs. (i)and(ii), we get
$x=\frac{1}{2} \times \frac{q E}{m} \times \frac{Y^{2}}{u^{2}}$
$\Rightarrow y^{2}=\left(\frac{2 m u^{2}}{q E}\right) x$
or $y^{2}=k x$
where, $k=$ constant This is an equation of a parabola.
So, the path of charge particle will be parabola.
