In the figure the charge $Q$ is at the centre of the circle. Work done is maximum when another charge is taken from point $P$ to
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The charge $q$ is fired towards another charged particle $Q$ which is fixed, with a speed $v$. It approaches $Q$ upto a closest distance $r$ and then returns. If $q$ were given a speed $2 v$, the closest distance of approach would be
$(a)$ Determine the electrostatic potential energy of a system consisting of two charges $7 \;\mu C$ and $-2\; \mu C$ (and with no external field) placed at $(-9 \;cm , 0,0)$ and $(9\; cm , 0,0)$ respectively.
$(b)$ How much work is required to separate the two charges infinitely away from each other?
$(c)$ Suppose that the same system of charges is now placed in an external electric field $E=A\left(1 / r^{2}\right) ; A=9 \times 10^{5} \;C m ^{-2} .$ What would the electrostatic energy of the configuration be?
Prove that electrostatic forces are conservative in nature and define electrostatic potential energy.
A point charge $2 \times 10^{-2}\,C$ is moved from $P$ to $S$ in a uniform electric field of $30\,NC ^{-1}$ directed along positive $x$-axis. If coordinates of $P$ and $S$ are $(1,2$, $0) m$ and $(0,0,0) m$ respectively, the work done by electric field will be $.........\,mJ$
Obtain the equation of electric potential energy of a system of two electric charges in external electric field.