Momentum Demonstration Lab
Cart and Medicine Ball
The force is greater when the ball first hits the person to get them to start moving, when they are already moving it is less force to keep them going.
difference between static and kinetic friction
Getting the Cart Started
There are two forms of friction, kinetic and static. If you try to slide two objects past each other, a small amount of force will result in no motion. The force of friction is greater than the applied force. This is static friction. If you apply a little more force, the object "breaks free" and slides, although you still need to apply force to keep the object sliding. This is kinetic friction. You do not need to apply quite as much force to keep the object sliding as you needed to originally break free of static friction.
What is Reducing the Velocity of the Cart?
Friction between the wheels and the floor. Also the force from ball to person.