# Graph of reaction force of bouncing ball

Let's consider a ball of mass 1kg with initial velocity 8m/s and final velocity -5m/s after bouncing off the floor, the duration of contact with the floor is 0.06s, therefore the average force is 217N.

Intuitively, the reaction force on the ball increases up to a maximum value then decreases because the instant the ball comes into contact with the surface, there's no change of momentum, and when the velocity becomes zero, the reaction force is the maximum. Reaction force then decrease as the ball increases its velocity and left the surface. How would a graph of reaction force against time look like?

• You say the reaction force will be maximal when the velocity is zero, but this doesn't have to be the case. For a perfectly elastic bounce it may be, but I think the more inelastic the bounce the earlier the maximum force will occur in relation to reaching velocity zero. In the extreme case, when the ball just splats inelastically onto the ground, velocity is zero at the very end, and maximal force is likely to have occurred at some earlier point. Mar 1, 2021 at 8:24

Shows the variation of force during the collision time $$\Delta t$$. As is obvious the average force is smaller than the peak force.