A charged particle of mass m and charge q is released from rest in an electric field of constant magnitude E. The kinetic energy of the particle after time t is

Question

A charged particle of mass m and charge q is released from rest in an electric field of constant magnitude E. The kinetic energy of the particle after time t is (A) (2 E2 t2/m q) (B) (E2 q2 t2/2 m) (C) (E q2 m/2 t2) (D) (E q m/2 t)

Tardigrade Admin · Accepted Answer

F=q E a=(F/m)=(q E/m) v=a t=(q E t/m) Kinetic energy =(1/2) m[(q E t/m)]2=(E2 q2 t2/2 m)

Q. A charged particle of mass $m$ and charge $q$ is released from rest in an electric field of constant magnitude $E$ . The kinetic energy of the particle after time $t$ is

$\frac{2 E ^{2} t ^{2}}{m q}$

$\frac{E ^{2} q ^{2} t ^{2}}{2 m}$

$\frac{E q ^{2} m}{2 t ^{2}}$

$\frac{Eq m}{2 t}$

$F = qE$
$a = \frac{F}{m} = \frac{qE}{m}$
$v = a t = \frac{qEt}{m}$
Kinetic energy $= \frac{1}{2} m [\frac{qEt}{m}]^{2} = \frac{E ^{2} q ^{2} t ^{2}}{2 m}$

Q. A charged particle of mass m and charge q is released from rest in an electric field of constant magnitude E. The kinetic energy of the particle after time t is

mq2E2t2​

2mE2q2t2​

2t2Eq2m​

2tEqm​