What you need

• An empty plastic bottle
• A balloon
• Scissors
• Sticky tape
• A target

Instructions

1. Carefully cut the bottom of the bottle off. Cut the neck off the balloon
2. Stretch the balloon over the bottom of the bottle. Don’t pull it tight
3. Tape the balloon in place around the bottle
4. Take aim at your target, pull back the centre of the balloon, hold the bottle steady and release!

Results and Explanation

A vortex of air is pushed out of the bottle by the balloon, ruffling everything it passes. How far will the vortex travel?

These experiments have not been specifically safety tested for home use but we believe them to be safe if the instructions are followed. Adult supervision or direction is recommended as appropriate. All experiments are carried out at your own risk.