demonstrations:efficiency_of_bouncing_balls
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
2 MINUTE EXPERIMENT - Ball Bounce! - HighSchoolScience101:
📄 Efficiency of a Ball - preproom.org: https://www.preproom.org/practicals/pr.aspx?prID=1054
📄 Bouncing Ball Efficiency: https://www.eips.ca/download/334080
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.)