Learn the basics of static electricity and electron transfer

Description:

Static electricity is the transfer of electrons from one material to another. You can see the effects of static electricity using balloons.

Equipment needed:

Two balloons inflated to the same size.

A light stick approximately two feet long (a couple of long matchsticks or chopsticks will do the trick)

Duct tape, masking tape, or some other heavier-duty tape.

String

A piece of cloth (wool works best). Something sock-sized or washcloth-sized will be fine.

The Digital Bits Science Lab Experiment:

If needed, create your “stick”. In the pictures below, I used a couple of long matchsticks, and just duct-taped them together. The goal is to create a stick long enough to suspend two balloons, and prevent them from easily touching a wall.

Cut two equal lengths of string, approximately 2 feet long. Tie each balloon to the stick using its own piece of string. Make sure the baloons are both at the same level.

Tape the stick on to a wall. Inside of a room entrance worked for me. This allows the balloons to extend into a room, while being held away from the walls.

The balloons may stick to each other slightly, or be repelled slightly, as we see here:

Now, rub one of the balloons with the wool, and let it drop. What happens? It may “bounce” away from the other balloon. It may stick to it.

Rub the second balloon with the wool, and let it drop. Both balloons should bounce away from each other. If you’ve built up enough of a charge, one balloon may even bounce off of the other balloon and stick to the wall:

What’s happening here?

Static electricity is the imbalance of electron charges. When you rub a balloon with the cloth, you’re actually moving electrons from the cloth to the baloon. The addition of the electrons gives the balloon a negative charge.

A couple simple rules when dealing with static electricity:

Objects will repel each other if they have the same charge. A balloon with a negative charge will repel other balloons with a negative charge. This is why the balloons pushed away from each other when we rubbed them both with the cloth.

Objects will attract each other if they have different charges.A balloon with a positive charge will attract other things with a negative charge. This is why rubbing a balloon attracts it to the wall – the wall has a more positive charge, which attracts the balloons more negative charge.

We use balloons in this experiment because they’re very light: the static attraction/repulsion is easier to see. But you can charge other things, too. See what other things you can make stick to the balloon (hint: you’ll have good luck with thin, light things, like paper, or hair).

Other articles related to this topic:

• Move a stream of water with a balloon and static electricity
• How to separate salt and pepper
• Build a balloon-powered mini-hovercraft
• Hot air takes up more space than cold air
• How to electroplate copper