Question

In the diagram shown, the charge + Q is fixed. Another charge +2q, is projected from a distance R from the fixed charge. Minimum separation between the two charges if the velocity becomes $\frac{1}{\sqrt{3}}$times of the projected velocity, at this moment is (Assume gravity to be absent)

• A. $\frac{\sqrt{3}}{2}R$
• B. $\sqrt{3}R$
• C. $\frac{1}{2}R$
• D. 4 R

Answer 1

Answer: (A)

$\frac{\sqrt{3}}{2}R$

Answer 2

By conservation of angular momentum about +Q charge m V × sin 30⁰ R = m × $\frac{V}{\sqrt{3}}$× d

̃ d = $\frac{\sqrt{3}}{2}$R