"Penny-in-a-Glass"

SCIENCE CONCEPT:

Newton's First Law of Motion: objects at rest remain at rest and objects in motion remain in motion unless acted upon by an outside force.

STUDENT OBJECTIVE:

The student will discover a part of Newton's First Law of Motion: an object at rest remains at rest unless acted upon by an outside force.

OVERVIEW:

The student will use a penny, a drinking glass, and a card to discover that an object at rest remains at rest unless acted upon by an outside force.

TEACHER TEXT:

PREPARATION TIME: 5 minutes

LESSON TIME: 15 minutes

TEACHER PREP:

Gather materials.

WORDS TO KNOW:

• strike
• flick
• rest

MATERIALS NEEDED:

• drinking glass
• 3x5 card
• penny

STEPS TO FOLLOW:

1. Place the 3x5 card over the upright glass.
2. Lay the penny in the center of the card.
3. Strike the edge of the card quickly with a flick of your index finger
4. Try this several times. Observe what happens. (Once you are able to flick the card forward with enough force, the penny tends to remain in mid air, then falls into the cup.)

WHY?:

Objects at rest tend to remain at rest unless acted upon by an outside force. This is called inertia. It is part of Newton's First Law of Motion. In this case, the penny was at rest on the card. When the card was flicked away with enough force this happened so quickly that the coin remained at rest in mid air due to inertia. The penny then falls when the card no longer holds it up.

ASSESSMENT: Can the student communicate what they observed?

4....The student is able to communicate that the penny was at rest and continued to stay at rest when the card was flicked away.

3....The student is able to communicate that the penny fell because the card no longer held it up.

2....The student is able to communicate that flicking the card made the penny fall.

1....The student is able to communicate that the penny fell into the glass.

Copyright © 1997 by Cislunar Aerospace, Inc. All Rights Reserved.