January 9 is National Static Electricity Day. This is a day to celebrate and explore how static electricity works and how we relate to it. Static electricity is a shock you get from touching something. It happens when electrons are “rubbed off” or “stolen” from objects.
Ways to demonstrate static electricity:
- Rub a balloon on your hair and stick it to the wall.
- Run a comb through your hair. Then use the comb to bend a thin stream of tap water.
- Wear rubber-soled shoes and rub your feet on carpet. Touch someone with your finger to give them a shock.
- Take clothing out of the dryer. You’ll notice some clothes are stuck together.
When you rub your head with a balloon, the balloon will stick to the wall. Why? The reason is that the friction made when two different objects are rubbed together creates static electricity. Three ways to tell if static electricity is present: it sparks and can shock you; it makes a crackling sound; it causes things to stick together.
Let’s use the first demonstration from above as our example. Rubbing the balloon on your hair causes the balloon to “steal” electrons from your hair. The balloon now has a buildup of electrons so it has a negative charge. Your hair has lost electrons, so it becomes positively charged. Because opposites attract, the negatively-charged balloon will stick to the wall. Alternatively, if there are enough electrons on the balloon, they will try to “jump” to the wall and will make a small spark.
Lightning Never Strikes Twice
Lightning is static electricity caused by nature. Lightning usually goes from cloud to ground. It is made when hot, moist air rises. The moisture in the air turns into rising ice crystals, which rub against falling hailstones high in the cloud. The hail “steals” electrons from the ice crystals, which causes the bottom of the cloud to have a large negative charge. When this buildup of electrons is large enough, the electrons will jump from the cloud to the positive ground below, creating a bolt of lightning.
Read more about lightning and how it works here, then answer the provided questions with this free worksheet.