An electron of mass ${m_e}$ initially at rest moves through a certain distance in a uniform electric field in time ${t_1}$. A proton of mass ${m_p}$ also initially at rest takes time ${t_2}$ to move through an equal distance in this uniform electric field. Neglecting the effect of gravity, the ratio of ${t_2}/{t_1}$ is nearly equal to
$1$
${({m_p}/{m_e})^{1/2}}$
${({m_e}/{m_p})^{1/2}}$
$1836$
Cathode rays travelling from east to west enter into region of electric field directed towards north to south in the plane of paper. The deflection of cathode rays is towards
A particle of mass $m$ and charge $(-q)$ enters the region between the two charged plates initially moving along $x$ -axis with speed $v_{x}$ (like particle $1$ in Figure). The length of plate is $L$ and an uniform electric field $E$ is maintained between the plates. Show that the vertical deflection of the particle at the far edge of the plate is $q E L^{2} /\left(2 m v_{x}^{2}\right)$
Compare this motion with motion of a projectile in gravitational field
Two identical positive charges are fixed on the $y$ -axis, at equal distances from the origin $O$. A particle with a negative charge starts on the $x$ -axis at a large distance from $O$, moves along the $+ x$ -axis, passes through $O$ and moves far away from $O$. Its acceleration $a$ is taken as positive in the positive $x$ -direction. The particle’s acceleration a is plotted against its $x$ -coordinate. Which of the following best represents the plot?
Figure shows tracks of three charged particles in a uniform electrostatic field. Give the signs of the three charges. Which particle has the highest charge to mass ratio?
A toy car with charge $q$ moves on a frictionless horizontal plane surface under the influence of a uniform electric field $\vec E .$ Due to the force $q\vec E$ , its velocity increases from $0$ to $6\,\, m s^{-1}$ in one second duration. At that instant the direction of the field is reversed. The car continues to move for two more seconds under the influence of this field. The average velocity and tlie average speed of the toy car between $0$ to $3$ seconds are respectively