Question

plz solve this question fast......

no spamming......​

Answer 1

Since the electron is moving from rest, by first equation of motion, we have,

$\longrightarrow\sf{u=at\quad\quad\dots(1)}$

where $\sf{v}$ is the velocity at a time $\sf{t}$ and $\sf{a}$ is the acceleration.

Given,

$\longrightarrow\sf{u=kt\quad\quad\dots(2)}$

From (1) and (2) we get the acceleration,

$\longrightarrow\sf{a=k}$

Or,

$\longrightarrow\sf{a=2\ m\,s^{-2}}$

The displacement traversed by the electron in $\sf{t}$ seconds is, by second equation of motion,

$\longrightarrow\sf{s=\dfrac{1}{2}\,at^2}$

$\longrightarrow\sf{s=\dfrac{1}{2}\cdot2t^2}$

$\longrightarrow\sf{s=t^2}$

In 3 seconds,

$\longrightarrow\sf{s=3^2}$

$\longrightarrow\sf{\underline{\underline{s=9\ m}}}$