|T H E N I H C A T A L Y S T||N O V E M B E R D E C E M B E R 2005|
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ZAPPED! STATIC ELECTRICITY
Under the right conditions, you'll throw sparks! It could be a little jolt or a very big one, but when it happens, you will be experiencing the effects of static electricity firsthand.
You've seen it or felt it before . . . the socks that magically stick together, that shock from touching a doorknob in winter or just touching someone else. It's all static electricity, and we're going to make a little bit of it today.
Try this when it's cool and dry: Put some shoes on and scuff your feet on the carpet a few times. Now if you touch a doorknob, or another person, you'll be shocked. Ouch! (The more you scuff, the more it will hurt, so be careful.)
But you don't have to wait for the perfect conditions, and you don't have to feel the pain in order to prove something is there. Let a balloon do the sticking for you!
What you'll need for this experiment:
1. At least two balloons, blown up and knotted the more the better
2. A wool sweater, rug, or cooperative fur-bearing animal (Cooperative is very important! If not, stick with the sweater.)
3. A wall
4. Talcum powder or flour
5. Hand lotion or hair conditioner
Now take the balloon and try to stick it to the wall (without tape, please). You'll see nothing but a falling balloon. Rub the balloon on the sweater for a few seconds and try again. It sticks! But for how long? Do you think the amount of time it sticks will increase the longer you rub the balloon?
Now if this isn't enough, take a look at fields. Instead of sticking the balloon to the wall, hold it over (but not touching) some flour or talcum powder. The powder will fly up and stick to the surface of the balloon. Twist the balloon around, picking up flour, and see if one side of the balloon picks up more than the other. Does it make a pattern?
Take another balloon and create the static charge again, but this time take a dab of hand lotion and put it on the balloon. Now hold it next to the powder. What do you think will happen?
Try sticking balloons to different materials: cloth, leather, metal, yourself. Can you predict which will stick longer?
What you've done by scuffing your feet or rubbing a balloon is to create a charge. Because there is no current (like plugs in the wall), it is called static. So the next time you're walking around and unexpected sparks fly, you'll know why!
Jennifer White, OD
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