Children naturally want to find out about the world around them – and with each new discovery comes more fascination and curiosity. Simple science activities can fuel your child’s curiosity, help them learn about their world through discovery, and develop their science skills and knowledge. Try this fun activity to help your child understand the concept of energy transfer and have some fun with bouncing balls!

What you will need

• A large heavy ball, like a basketball
• A tennis ball or other small sized ball
• Some space with a firm, flat ground – try this activity outside!

What to do

1. Ask your child to drop the basketball from shoulder height and take note of how high it bounces back up to on their body (for example, knees, hips or elbow).
2. Repeat Step 1 with the tennis ball.
3. Ask your child to hold the two balls up to shoulder height with the tennis ball on top of the basketball – they will need to keep one hand under the basketball and the other on top of the tennis ball.
4. Get your child to let go of both the balls at exactly the same time and watch what happens – if the balls are dropped at the same time, the tennis ball should bounce off the basketball and fly high into the air, and the basketball should hit the ground and not bounce, almost like it is flat. (They might need to practise this a few times to get it right!)

What’s happening?

Lifting a ball into the air before dropping it gives it a type of energy called ‘potential energy’ – which means the ball has the potential to do some work.

When you drop the ball, it gains ‘kinetic’ energy (the energy of motion) and loses its potential energy.

When the two balls are dropped at the same time, they hit each other (collide) just after they hit the ground, and a lot of the kinetic energy in the larger ball is transferred to the smaller ball. This gives the smaller ball more energy, so it bounces off further! It also means the larger ball has almost no energy left, so it cannot bounce far off the ground at all.

Energy transfer is an important scientific concept that has many applications in daily life. To extend this activity, talk to your child about times when they have noticed energy transfer in real life – for example, when they hit a ball with a bat!