Question

A mass m moves with a velocity $\upsilon$ and collides in-elastically with another identical mass. After collision first mass move with velocity $\frac{\upsilon }{\sqrt{3}}$ in a direction perpendicular to the initial direction of motion. Find the speed of second mass after collision.

• A. v
• B. $\sqrt{3v}$
• C. $\frac{2v}{\sqrt{3}}$
• D. $\frac{\upsilon }{\sqrt{3}}$

Answer 1

The correct option is C $\frac{2v}{\sqrt{3}}$

$m\upsilon =m{\upsilon }^{\prime }cos\theta ,0=\frac{m\upsilon }{\sqrt{3}}-m{\upsilon }^{\prime }sin\theta$
or ${\upsilon }^{-2}[co{s}^2+si{n}^2\theta ]={\upsilon }^2+\frac{{\upsilon }^2}{3}$ or ${\upsilon }^{\prime }=\frac{2\upsilon }{\sqrt{3}}$