Two particles each of mass $m$ and charge $q$ are separated by distance $r_1$ and the system is left free to move at $t = 0$. At time $t$ both the particles are found to be separated by distance $r_2$. The speed of each particle is
Two particles each of mass $m$ and charge $q$ are separated by distance $r_1$ and the system is left free to move at $t = 0$. At time $t$ both the particles are found to be separated by distance $r_2$. The speed of each particle is
- A
$\frac{{qm}}{{4\pi {\varepsilon _0}{r_1}{r_2}}}$
- B
$\frac{q}{{{r_1}{r_2}\sqrt {(r_2^2 - r_1^2)/4\pi {\varepsilon _0m}} }}$
- C
$\frac{\sqrt 2q}{{{r_1}{r_2}\sqrt {(r_2^2 - r_1^2)/4\pi {\varepsilon _0m}} }}$
- D
none of these
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