question_answer

In free space, a particle A of charge \[1\mu C\]is held fixed at a point P. Another particle B of the same charge and mass \[4\mu g\]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 : \[\left[ \text{Take}\frac{1}{4\pi {{\varepsilon }_{0}}}=9\times {{10}^{9}}N{{m}^{2}}{{C}^{-2}} \right]\] [JEE Main 10-4-2019 Afternoon]

A) \[2.0\times {{10}^{3}}m/s\]

B) \[3.0\times {{10}^{4}}m/s\]

C) \[1.5\times {{10}^{2}}m/s\]

D) \[1.0\,m/s\]

Correct Answer: A

Solution :

[a]