Dollar Bill and the Boittles

Presenter: Tony Wayne, Albemarle HS, twayne@albemarle.org

Va. SOL:

• PH.5: The student will investigate and understand the interrelationships among mass, distance, force, and time through mathematical and experimental processes. Key concepts include

…Newton's laws of motion;

National Standards:

Newtonian Mechanics

Topic/Concept

Newton’s 1^st Law of Motion: “An object at rest remains at rest…”

Materials

· 2 GLASS bottles

· Dollar bill

· Duct tape or clear sealing tape

Safety Considerations

Have a spotter nearby to catch the top bottle if it falls.

Presentation

Balance a bottle on top of another with a dollar bill between them. The bottle should be on the round symbol between the portrait and edge. With you fingers feel if the bottles line up on top of each other. Using your left hand hold the bill still. Be careful not to move the bill when you hold it. Hold it tight. Quickly chop the portrait on the bill with the index finger on your right hand. If the bottles line up, the top bottle will not move off the bottom bottle and the dollar will be in your left hand.

How the physics is demonstrated

This illustrates the definition of inertia. The bottle on top has mass and resists a change in motion. It resists enough so that pulling the bill out does not cause the bottle to move.

Construction and Tips Regarding the Demonstration

Wrap the bottles in tape. If a bottle does fall, this will reduce the odds of it being broken. …Or at least broken into small pieces.

Sources & References

None