A r c h i v e d I n f o r m a t i o n
Have you ever been shocked when you walked across a rug or touched a light switch? Wait until a cool, dry day to learn about static electricity.
What you'll need
A cool, dry day
2 round balloons (inflated and tied)
2 20-inch pieces of string
1 wool or acrylic sock.
1 mirror (or more)
1 friend (or more)
Your science journal
What to do
All materials contain millions of tiny particles, called protons and electrons, that have electric charges. Protons have positive charges, and electrons negative ones. Usually, they balance each other, but sometimes when two surfaces rub together, some of the electrons rub off one surface onto the other and we can have static electricity. Materials with like charges (all positive or all negative) move away from each other; those with opposite charges attract each other.
- Tie a string to each inflated balloon.
- Rub a balloon on your hair for about 15 seconds. Be sure to rub around the whole balloon.
What happens to your hair?
What happens when you bring the balloon back close to your hair?
- Rub the balloon on your hair again and have a friend (or parent) do the same with the other balloon.
- Each of you hold the string to 1 balloon, letting the balloons hang freely, but without letting them touch anything.
- Slowly move the 2 balloons toward each other, but don't let them touch.
What do you see?
Do the balloons push away from each other, or do they pull toward each other?
- Place your hand between the two hanging balloons.
- Place a sock over 1 hand and rub 1 balloon with the sock. Then let the balloon hang freely. Bring your sock-covered hand near the balloon.
- Try rubbing both balloons with the sock and then let them hang near each other.
What happens now?
- Look for other examples of static electricity around the house.
Have you ever felt a shock when you touched a metal doorknob on a cold winter day? What often happens when you remove the clothes from the dryer?