Given: Mass of the ball is
The situation is shown in the figure below.
Here, AO is the original path of the ball, OB is the path followed by the ball after deflection. Angle AOB is the angle between the incident and deflected paths of the ball.
From the figure,
The horizontal components of velocities suffer no change. The vertical components of velocities are in the opposite directions.
Impulse imparted to the ball is given as,
Where,
By substituting the given values in the above expression, we get
Thus, the impulse imparted to the ball is