An object at rest will remain at rest, and an object in motion (with constant velocity) will continue in motion (with constant velocity), unless it is acted upon by a net external force.

Newton's First Law

Use of the PAScar Dynamics System.

Demonstrate objects at rest remain at rest

To demonstrate that an object at rest will remain at rest, place a dynamics cart loaded with 2 mass bars at rest on a 1.2 m Dynamics Track. Place an object such as a cup on the table in front of the cart to mark the position of the cart. Then take hold of one end of the track and quickly pull the track horizontally about 25 cm. The cart will roll on the track but it will remain at rest with respect to the cup and table because there is no net force on the cart.

Here's What You Need:

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Demonstrate objects in motion remain in motion

Here's What You Need:

Give a glider a push on an air track, and the glider will just keep on moving at constant velocity until it hits the end of the track.

Or give a hover puck a push on the floor.

Or for a bigger demonstration, give the hovercraft with a person a push and watch them glide.