Effect of Friction on the Constant Velocity of a Moving Object (page 2)
Other Things to Try
This experiment can be done using a person riding in style in a Hovercraft, as pictured in Figure 1-3. This can be done as an interesting way to do the previous experiment or just simply for the fun of doing it.
Because of the nearly frictionless motion, the person moves at constant velocity and makes a perfect object to measure at various speeds. You can purchase a Hovercraft (PASCO, part number ME 9838).
A Hovercraft can also be built by following these basic steps:
- Drill a hole in the center of a 3-to-4 foot diameter piece of plywood.
- Cut a hole halfway between the center and the edge just large enough to fit the end of a leaf blower.
- Staple a plastic sheet to the bottom of the Hovercraft. Trim off the excess plastic.
- Insert a bolt from the underside of the Hovercraft, through a plastic spacer (made from a plastic coffee-can lid). Attach the bolt through washers on the top and bottom, and then secure it with a nut.
- Tape all the seals between the leaf blower and the plywood, and the plastic sheet and the plywood, to make them as airtight as possible.
- Cut several approximately 2-inch diameter vent holes in the plastic sheet a few inches from the outer circumference of the plastic spacer.
- With the leaf blower turned on, a cushion of air should enable a person to move with a minimum of friction.
Detailed plans can be found at http://amasci.com/amateur/hovercft.html.
The tendency of a moving object to keep moving is called inertia, which is addressed in Newton's first law. This is the subject of experiments that follow.
Constant velocity is represented by a straight line on a distance versus time graph. The slope of the line is equal to the average velocity.
Warning is hereby given that not all Project Ideas are appropriate for all individuals or in all circumstances. Implementation of any Science Project Idea should be undertaken only in appropriate settings and with appropriate parental or other supervision. Reading and following the safety precautions of all materials used in a project is the sole responsibility of each individual. For further information, consult your state’s handbook of Science Safety.