Teaching activity - Bouncing balls
This resource for level 3–4 students supports the science capability "gather and interpret data".
About this resource
Students explore how and where a ball bounces and how this is determined by its elastic properties (how much it can be squashed and how readily it recovers), the effect of friction on spin, and how it is thrown.
Teaching activity-Bouncing balls
Curriculum Links
Level 3 and 4
Nature of Science: Investigating in science
Students will:
- build on prior experiences, working together to share and examine their own and others’ knowledge
- ask questions, find evidence, explore simple models, and carry out appropriate investigations to develop simple explanations.
Level 3 and 4
Physical World: Physical enquiry and physics concepts
Students will:
- explore, describe, and represent patterns and trends for everyday examples of physical phenomena, such as forces
Level 3 and 4
Material World: Chemistry and society
Students will:
relate the observed, characteristic chemical and physical properties of a range of different materials to technological uses and natural processes.
Mātauranga Māori
Within te ao Māori, games of skill such as Ki-o-rahi and Tapu Ae involve understanding how balls behave in response to force and direction. Games such as Tītī tōrea played with tī rākau involve understanding the flight paths of sticks as they move through the air between partners. Kōruru is another game where the flight path of the knucklebone needs to be correctly planned and executed in order to successfully play the game. These provide rich contexts in which students learn about how balls behave.
Resources to go further:
Resource overview
How and where a ball bounces is influenced by its elastic properties (how much it can be squashed and how readily it recovers) and how it is thrown, as well as the effect of friction on spin.
In this activity, students may discover that a well-constructed investigation can still produce unexpected results. These surprises need to be considered carefully and tested further.
There may also be more than one explanation for the results of an investigation. Open-mindedness is important in science.
Learning Intentions / Success Criteria
Students will:
- make predictions based on their prior knowledge and testing
- make careful observations of how the ball bounces to determine where the catcher should stand (gather and interpret data)
- create an explanation or explanations for their results (use evidence).
Learning Activity
- a range of balls of similar size and shape, some hard and some soft. For example:
- table tennis ball
- tennis ball
- golf ball
- squash ball
- solid rubber ball
- high-bouncing plastic ball
- a table or desk, preferably rectangular, with a smooth undersurface
- a hard, uncarpeted floor surface on which to bounce the balls
- When a ball is lifted up it has potential energy.
- When a ball is dropped, gravity pulls it towards the floor.
- As it is dropped, the ball gains the energy of motion – kinetic energy.
- When it hits the ground, this energy needs to be dispersed, making the ball change shape – it deforms and is squashed. Energy is also dispersed in the form of heat and sound energy.
- As it is squashed, the ball’s particles spread further apart in some areas of the ball and squeeze closer together in others.
- As these particles are stretched and squeezed, they collide with each other.
- The amount of bounce a ball has is related to the elastic properties of the ball material, how the ball changes shape, and where the ball’s energy goes.
- Describe how different balls bounce - do they bounce differently?
- Why might different balls bounce differently?
- What types of materials are the balls made of? Which ones are bouncy, and which ones are less bouncy?
- When you bounce a ball, is it possible for you to predict where the ball will travel? What games do you play that depend on predicting where and how a ball will bounce?
- Explain to students that they will be conducting a scientific investigation.
The investigation will focus on predicting where the catcher needs to stand to catch the ball. To do this, they will need to observe the properties of balls and how these properties determine the amount of bounce.
The focus will be on:- elastic properties – how much it can be squashed, how readily it recovers
- how the ball is thrown.
- Choose two students, thrower and catcher, to stand at each end of the table/desk. Alternatively, construct a target to place at the far end of the table. See Materials that come with this resource to download Predicting Ball Bounce (.pdf), a diagram illustrating how to conduct the activity.
- Have the thrower choose a ball, and prepare to bounce it between the legs of the table/desk – that is, aiming at a midpoint between the two nearest legs – so that it will then rebound off the undersurface of the desk and to the catcher.
- While the thrower is preparing, the rest of the class need to:
- record their prediction, with reasons, of where the catcher will need to stand to receive the ball, or where, if using a target, the ball will strike the target
- discuss and decide how to test – throwing technique, speed, where the thrower stands – and record the outcome.
- Have the thrower throw the ball.
- Get the students to compare the result with their prediction.
- Repeat for the other balls, recording predictions of where the catcher should stand and why, testing, and recording the outcomes.
- Students in pairs create their own investigation using an option of:
- the same ball, several times to test consistency of results
- different balls, same throwing technique
- different throwing techniques using the same ball – students need to consider which variable is changing and which variable is remaining the same.
- During investigation, get the students to:
- tabulate their prediction and results (teachers may like to provide a template for data recording)
- identify which types of ball did or didn't follow predictions
- when recorded, consider ways to improve or change their testing/recording methods, for example, by marking the ball with chalk.
- Explore further by getting students to search for explanations for their observations.
- Have them present and support their explanations to the class.
- Did you get the results you expected?
- If not, what else did you do to help you find out what was happening?
- What factors seem more important in ball bounce – the ball size, shape, or composition?
- Now that you’ve carried out these experiments, can you use what you’ve found out to test a different range of similar-sized/shaped balls, for example, a billiard ball, a wooden ball, a petanque ball, a cricket ball, or a baseball?
- Based on your experience, predict how you think these different balls will behave. Is how the ball is used in the game related to the way it behaves?
Why do balls bounce? – Science Sparks – bouncing balls on different surfaces
Bouncing balls – AT (Year 8) | The Australian Curriculum (Version 8.4) – creating a fair test: drop height vs bounce height
Bouncing Ball Physics: What is Elasticity? Education.com – investigating the elasticity of balls
