Question

A ball strikes a smooth horizontal ground at an angle of ${45}^{\circ }$ with the vertical. What cannot be the possible angle of its velocity with vertical after the collision? (Assume $e\le 1$)

• A. ${45}^{\circ }$
• B. ${30}^{\circ }$
• C. ${53}^{\circ }$
• D. ${60}^{\circ }$

Answer 1

The correct option is B ${30}^{\circ }$

Since $e\le 1$ velocity of approach cannot be less than velocity of separation,
i.e., vertical component of velocity cannot increase. The horizontal component will remain the same.
Hence angle with vertical cannot decrease.