You will need:
Instructions1. Make sure the can is empty and dry
2. Blow up the balloon.
3. Rub the balloon vigorously on the head of your volunteer, until their hair starts to stand on end.
4. Lie the soft drink can down on its side on a flat surface, like a table.
5. Hold the part of the balloon that was touching your volunteer’s head close to the coke can, but don’t touch it. You should see it roll towards the balloon, seemingly by itself!
6. Try getting to roll and then reverse the direction of motion without touching it.
7. All static electricity experiments work better on dry days (less humidity drawing charge away from the objects you're using).
Everything in the universe is made of atoms: tiny particles that have positively charged parts (protons) and negatively charged parts (electrons) plus some neutral parts (neutrons). Please note that the real structure of the atom is outside the scope of this webpage; if you want a quick high school description of sub-atomic particles check out the Standard Model description on the CERN website or for a primary school version of the structure of the atom click here.
When you rub the balloon on your hair, some of the electrons in your hair jump ship onto the balloon. This leaves your hair with more protons than electrons, and therefore an overall positive charge. Similarly, the balloon now has too many electrons, and so has a negative charge. These opposite charges attract, which is why we see your hair stand up, trying to get close to the balloon.
If you want to get a real idea of atom structure here is a link to
When we put the charged up balloon near the soft drink can, there are two results.
First, the negative charges on the balloon move as far away from the can as possible: similar charges repel! Secondly, the negative charges on the can move as close to the positive charges on the balloon as they can get, creating an attractive force that moves the can along the table towards the balloon.
The charge we create in the balloon is called static electricity. It’s the same charge that gives us a zap on a slide, swing set or trampoline. It’s also the same charge that causes massive lightning bolts. Instead of a balloon and hair rubbing against each other, in a cloud it is tiny particles of ice that bump into each other and cause the build-up of charge. When there’s enough charge in the cloud, it’s unleashed as a lightning bolt. A moderate thunderstorm can produce more than 700 megawatts of power, which is more than any of the generators at Loy Yang power station in Gippsland, Victoria.
Year 4 Science
Forces can be exerted by one object on another through direct contact or from a distance (ACSSU076)
Electricity teaching resources