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An electron $(q_1)$ is moving in free space with velocity $10^5$ m/s towards a stationary electron $(q_2)$ far away. The closest distance that this moving electron gets to the stationary electron before the repulsive force diverts its path is ____________$\times 10^{-8}$ m.

[Given, mass of electron $m=9.11\times 10^{-31}$ kg, charge of electron $e=-1.6\times 10^{-19}$ C, and permittivity $\varepsilon _0=(1/36\pi)\times 10^{-9}$ F/m]