# Science at Home

Keep learning in place and at your pace with science activities and topics you can access anytime.

physics and engineering

## Roller Coaster

Learn about energy as you send a marble through a roller coaster that you design.

## Materials

• Marbles or small balls
• About 6 feet of flexible tubing, such as ¾-inch
foam pipe insulation
• Plastic cup
• Scissors
• Various supports, such as boxes, paper towel
tubes or books

## Directions

1. Cut the tubing in half. This doubles the amount of “track” for the roller coaster.
2. Your “car” (the marble) needs kinetic energy at the beginning of the roller coaster so that it can make it through the entire course. How should the tubing for the beginning of the roller coaster be positioned? Use tape and various supports to create the starting point.
3. Use the tubing, tape and supports to build the rest of your roller coaster. Try to include at least one loop, hill and jump.
4. Put the plastic cup at the end of the course. The challenge is to get the marble to land in the cup.
5. Place your marble at the beginning of your roller coaster and let it go. Did it work? Figure out what went wrong, and make adjustments to your course as needed.

## What's happening?

A roller coaster demonstrates kinetic energy and potential energy. A marble at the top of the track has potential energy. When the marble rolls down the track, the potential energy is transformed into kinetic energy. Real roller coasters use a motor to pull cars up a hill at the beginning of the ride. Cars that are stopped at the top of the hill have potential energy. As the car rolls down the hill, the potential energy becomes kinetic energy.

## Extensions

Once you get your roller coaster to work, try starting the coaster at a higher point and see what happens. Try a different design by adding more loops, hills or curves to your course.

Find the velocity of the marble. Velocity = distance travel / time. Measure the length of the track in centimeters. Use a stopwatch to record the time it takes a marble to complete the run in seconds. So v = cm / sec

## Vocabulary

Kinetic energy
Energy from motion

Potential energy
Stored energy that transforms into kinetic energy