Question

$AB$ an $L$ shaped obstacle fixed on a horizontal smooth table. A ball strikes it a $A$, gets deflected and restrikes it at $B$. If the velocity vector before collision is $v$ and coefficient of restitution of each collision is $e$, then the velocity of ball after its second collision at $b$ is

• A. $e^2\overrightarrow{v}$
• B. $-e^2\overrightarrow{v}$
• C. $-e\overrightarrow{v}$
• D. $Datainsufficient$

Answer 1

The correct option is C $-e\overrightarrow{v}$

$VR=\sqrt{e^2{\overrightarrow{v}}^2{\sin }^2\theta +e^2{\overrightarrow{v}}^2{\cos }^2\theta }$

$=-e\overrightarrow{v}$

Hence,

option $\left(C\right)$ is correct answer.