# Projectile strikes a wall

**Classical Mechanics**Level 3

A ball is thrown horizontally from the top of a tower of unknown height. Ball strikes a vertical wall whose plane is normal to the plane of motion of ball. Collision is elastic and ball falls on ground exactly at the midpoint between the tower and the wall. Ball strikes the ground at an angle of \(30^{\circ} \) with the horizontal. The distance between the tower and the wall is \( l=8\sqrt{3} \,\text{m} \). Find the height of tower, \(H\), **in metres**.

**Note:** The path in the image isn't the exact trajectory of the ball, its drawn poorly.