The Runaway Drinks Can experiment is a simple introduction to physics which uses items from around the home to show the effects of atoms.
What you will need
- 1 balloon
- 1 empty drinks can (330ml)
- Wool (eg: pullover, jumper, blanket) or cotton item
How to do it
- Fully inflate the balloon and tie it off.
- Rub the balloon about 20 times on something made of wool or cotton (or even your head!).
- Place the empty drinks can on its side on a flat table.
- Put the balloon near the can and watch it roll towards the balloon. Keep moving the balloon away and the can will follow.
What is happening?
All material is made of atoms. Atoms are made from even smaller parts called sub-atomic particles which are split into three types:
- Electrons (negatively charged)
- Protons (positively charged)
- Neutrons (neutrally charged)
Different materials have varying degrees of wanting to collect electrons (called ‘Triboelectricity’). Some of the least electron hungry atoms are fur, wool and human hair, while the most electron hungry are things like wood and rubber.
Balloons are made from rubber latex which has a great affinity to collect electrons which are negatively charged. By rubbing the balloon on a material that has less affinity to hold electrons (ie wool or human hair), the electrons are passed over. If the tin can has a positive or neutral charge, it will be attracted to the balloon.
Share your experiment...
All experiments must be conducted in the safest possible way. An adult must be present wherever it states one is required. Never do anything dangerous with chemicals or fire for your sake and those around you.