In free space, a particle A of charge 1 μC is held fixed at a point P. Another particle B of the same charge and mass 4 μg is kept at a distance of 1 mm from P. If B is released, then its velocity at a distance of 9 mm from P is:[\({\rm{Take}}\;\frac{1}{{4{\rm{\pi }}{_0}}} = 9 \times {10^9}{\rm{\;N}}{{\rm{m}}^2}{{\rm{C}}^{ - 2}}\)]

• A. 1.0 m/s
• B. 3.0 × 104 m/s
• C. 2.0 × 103 m/s
• D. 1.5 × 102 m/s