Efficiency of Bouncing Balls
Materials: ★☆☆ Easy to get from supermarket or hardware store
Difficulty: ★☆☆ Can be easily done by most teenagers
Safety: ★☆☆ Minimal safety procedures required
Categories: Energy
Alternative titles: Energy Efficiency of Balls
Summary
Different types of balls are dropped from a set height, and the height of their bounce is measured to determine their efficiency in conserving energy during impact.
Procedure
Gather a selection of balls such as tennis, squash, table tennis, and cricket balls.
Measure a specific drop height using a metre rule.
Drop each ball from this height onto a flat surface and record the height of the first bounce.
Repeat the process several times for accuracy and calculate the average bounce height.
Determine the efficiency of each ball using the formula:
Efficiency = (Bounce Height ÷ Drop Height) × 100%.
Compare results between different types of balls to find which is most efficient.
Links
Variations
Investigate how heating a squash ball with a hairdryer affects its bounce efficiency.
Try dropping balls onto different surfaces to observe how surface texture and hardness influence energy loss.
Use a high-speed camera or slow-motion recording to analyze the motion and deformation of the ball during impact.
Safety Precautions
If using a hairdryer to heat a ball, do not overheat it.
Handle hot equipment carefully and allow the ball to cool before touching.
Conduct tests in an open area to avoid injury from rebounding balls.
Questions to Consider
What type of energy conversion occurs when a ball bounces? (Gravitational potential energy converts to kinetic energy and then to elastic potential energy during impact.)
Why do some balls bounce higher than others? (Because they lose less energy to heat, sound, and deformation.)
How does temperature affect the efficiency of a ball? (Warmer balls, such as heated squash balls, often bounce higher due to increased elasticity.)
Would a perfectly efficient ball ever stop bouncing? (No, if it were 100% efficient, it would bounce back to the same height indefinitely, though this is impossible in practice.)