This simulation shows the connection between force and motion.
A box is placed on a frictionless horizontal surface. You can adjust the mass of the box and the horizontal force applied to the box. Note that the free-body diagram is shown. The blue arrow is the normal force applied to the box by the surface; the green arrow is the force of gravity applied to the box by the Earth, and the red force (if there is one) is the force you control with the slider.
Apply a non-zero force to the box and press Play. You should see the box start to move. What happens when you set the force back to zero? How can you make the box stop moving?
Simulation written by Andrew Duffy, and first posted on 9-16-2017.
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