Year 7 Science · Unit 3 · Lesson 10
Challenge Worksheet
Learning Goals
Design a mini-experiment
A scientist wants to test: "How much of a bouncing ball's kinetic energy is converted to sound energy?" They plan to use the height-drop method — dropping the ball from different heights and listening to the loudness of the bounce. Plan the investigation below.
| What I will change (independent variable) | |
| What I will keep the same (controlled variables — list at least 3) | |
| What I will measure (dependent variable) | |
| My prediction — what do I expect to happen as drop height increases? | |
| How would I know if my prediction is wrong? | |
| One major limitation of using "listening to the sound" as my measurement method |
The ball never bounces back to its original height. Using the law of conservation of energy, explain where the "missing" energy goes. Name at least two forms it is converted into.
1. A student suggests using a sound-level meter (decibel meter) app on a phone to measure the loudness of each bounce. Evaluate this suggestion: what is one advantage and one disadvantage of this approach?
2. If you dropped a rubber ball and a steel ball from the same height, predict which would make a louder sound on impact and which would bounce higher. Use your understanding of energy forms to justify both predictions.
Wrap Up
In one sentence, what was the main idea of this lesson?