Q.
Two negatively charges particles having charges $e_{1}$ and $e_{2}$ and masses $m_{1}$ and $m_{2}$ respectively are projected one after another into a region with equal initial velocity. The electric field $E$ is along the $y$-axis, while the direction of projection makes an angle a with the $y$-axis. If the ranges of the two particles along the $x$-axis are equal then one can conclude that
A) $e_{1} = e_{2}$ and $m_{l} = l$
B) $e_{1} = e_{2}\ $only
C) $m_{1} = m_{2}$ only
D) $e_{1}m_{1} = e_{2}m_{2}$
Explanation
(a) Here, effected gravitational acceleration is
$g^{'} = \frac{mg - qE}{m}$
$\therefore\ R = \frac{v_{0}^{2}\sin{2\alpha}}{g'}$
It means, $g’$ for both particles are same
This is possible when
$m_{1} = m_{2}$ and $e_{1} = e_{2}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.