Rolling on Different Surfaces (Indoors)

Explore how different ﬂoor surfaces affect how far a ball travels after leaving a ramp.

Materials

two identical ramps or one very wide ramp (cardboard, foam core, wood)
pairs of identical balls (for example: 2 tennis balls, 2 ping pong balls, 2 golf balls, etc.)
a rug
masking tape
camera or video camera

Key Science Concepts

The motion and speed of a rolling or sliding object is affected by the shape and texture of the object and the texture of the surface on which it is rolling or sliding.

Vocabulary

Encourage terms such as surface, texture, bumpy, smooth, farther, closer, bigger, smaller, heavier, and lighter as well science process words such as observe, compare, same, different, change, and test.

Directions

Point out two contrasting ﬂoor surfaces in your room: for example, smooth tile and a rug. Have children feel and describe the two surfaces. Ask them to predict on which surface a ball would roll farther. Why do they think that is?
Set up two identical ramps (or one wide ramp) side by side: one on the smooth ﬂoor surface and one on a rug. Provide two identical balls. Say, “1, 2, 3, Go!” and let two children gently release the balls so they roll down the ramps. Let the balls roll until they come to a natural stop. Have the group talk about what they notice and help them mark the distance each ball rolled with masking tape.
Try the same experiment several times. Are the results the same or almost the same each time?
Encourage children to try the experiment with other sets of identical balls.

Reflect and Share

After children have experimented with the ramps on the ﬂoor and the rug, encourage them to report on what they observed, share their discoveries, and pose other questions that they want to explore..