Video: Instructor’s video
Description: This demonstration illustrates newtons laws.
Ask for two volunteers; a light person and a heavy person.
Align the carts head on, and have a person get on each cart. Have each of them hold one end of a rope.
Have each pull on the rope and observe what happens. The force in the rope is the same (Newton’s third law).
Note that the light person went a greater distance and had a greater acceleration (Newton’s second law).
You can also have one person hold the rope, while the other pulls on it. Observe that both move.
Note: Hold the carts steady when your assistants are getting on.
When they pull the rope, make sure it does not get caught under their wheels.