The Bouncing Ball Energy Test

The Bouncing Ball Energy Test

Balls bounce because of energy. When you hold a ball up high, it has potential energy. This means the ball is storing energy because it is above the ground. When you let go, the ball falls. Now, the stored energy turns into kinetic energy—the energy of moving things.

When the ball hits the ground, something interesting happens. The ball squishes for a moment. The energy from moving becomes elastic potential energy. This is energy stored when something is squeezed or stretched, like a rubber band. The ball then springs back to its shape and bounces up. As it rises, that elastic energy turns back into kinetic energy, and then into potential energy as the ball reaches its highest point.

Balls never bounce back to the exact height they were dropped from. Some energy is always lost. But 'lost' energy isn’t gone—it just changes form. When the ball hits the ground, some energy turns into heat and sound. That’s why you hear a bounce!

Scientists test bounciness by dropping different balls (like tennis balls, basketballs, golf balls, and super balls) onto different surfaces (like concrete, grass, or carpet). They measure how high the ball bounces compared to how high it was dropped. The bounciness is the ratio of bounce height to drop height. For example, if a ball is dropped from 100 cm and bounces back to 60 cm, its bounciness is 60%.

People use this science in real life. Sports balls are designed to bounce in special ways. Engineers use these ideas for things like car shock absorbers and running shoes with bouncy soles. In every bounce, the ball pays a little energy 'tax' to the floor in the form of heat and sound, so it doesn’t bounce as high each time.

Interesting Fact: If you try different balls and surfaces, you might find a super ball on concrete gives the best bounce!