In free space, a particle A of charge 1 μ C is held fixed at a point P. Another particle B of the same charge and mass 4 μ g is kept at a distance of…

In free space, a particle A of charge $\displaystyle 1 \mu \mathrm{C}$ is held fixed at a point P. Another particle B of the same charge and mass $\displaystyle 4 \mu \mathrm{~g}$ is kept at a distance of $\displaystyle 1$ mm from P . If B is released, then its velocity at a distance of $\displaystyle 9$ mm from P is : $$\left[\text { Take } \frac{1}{4 \pi \epsilon_{\mathrm{o}}}=9 \times 10^9 \mathrm{Nm}^2 \mathrm{C}^{-2}\right] $$