In this activity, students learn about energy transfer by observing a demonstration involving balls of different size and elasticity.
Elasticity is the tendency of something to return to its original shape if it gets deformed. If something is very elastic, it will do this quickly and with great force. If it's not so elastic, it will do it slowly and with not as much force.
The tendency of a material to return to its original shape makes it possible for an object to bounce. When a highly elastic object hits the ground, it changes shape. Instead of staying in its changed form, an elastic object pushes against the ground to revert to its original shape. This gives the elastic object its bouncy zing, which will vary depending on the material the object is made of.
In this demonstration, energy from one, heavier bouncing ball is transferred into a smaller, lighter bouncing ball, causing the smaller ball to rocket much higher into the air.
Activity adapted from Science Kids.