Tuesday, March 17, 2009

Creating Static

As part of my unit on electricity, I decided to talk a little about static electricity as well. Static electricity is a fun concept, there are lots of experiments to demonstrate it in action. And while I had pages and pages of fun demonstrations, I wanted to at least introduce the some of the science behind it.

So, I did some research. As I read through the information, my brain slowly started to go to mush. If this stuff is boring me to tears, how will I explain it to a room full of young children? I started again, trying to figure out the key things I wanted to get across. Atoms (ok, we had talked about those); protons and neutrons (covered those, too); electrons (yep, also familiar territory); positive and negative charge (ack! what? my brain hurts).

I decided to touch on the very basic aspects of static electricity, using the terminology we had already touched on while talking about electricity. Using my atom diagram, I explained that sometimes when you rub two items together (I used a balloon on the carpet), the electrons from one item will jump to another item, causing it to have more electrons than it needs. Now these extra electrons need a place to go, and when the item with the extra electrons find another item with no extra electrons, the electrons will jump to the other item, making the other item stick to the first item. Ok - after all of that does your brain hurt?

As I blathered on, I used the balloon and the carpet. As I rubbed the balloon on the carpet, I explained how the balloon was getting extra electrons. Then I held the balloon over some scraps of tissue paper, and as the tissue paper jumped onto the balloon, I said, "Now the balloon is giving its extra electrons to the tissue paper." I demonstrated the same concept by sticking the balloon to the ceiling, to the wall, as well as holding the charged balloon over a child's head to make his hair stand on end. I eventually gave each child their own balloon, and they all rubbed it on the carpet to "get extra electrons", and then wandered around the room trying to figure out "where they could get rid of the extra electrons"..

To illustrate the concept of having too many electrons (and to toss in a little math), I brought out a simple balance and a bunch of milk bottle caps with the letter "E" on them. As I rubbed the balloon on the carpet, I added "electrons" to one side of the balance until it tipped to heavy side. "Now the balloon has too many electrons". As the tissue paper stuck to the balloon, I removed "electrons" from the heavy side of the balance, until the two sides were once again even. The kids then had a good time playing with the balance, and figuring out exactly how many electrons were too many. (Not being all that accurate of a balance, that number kept changing.)

We also played with static electricity using a plastic spoon and pepper...rub the spoon on carpet (getting extra electrons), then hold the spoon over the pepper (getting rid of the electrons), and the pepper jumps up to the spoon. Pretty cool.

There are a kajillion activities to illustrate static electricity. As this was my first time doing this, I chose only to touch lightly on this topic. Next year, I am thinking I will spend a little more time, and go a little deeper (positive and negative charges? possibly...). Possibly introduce magnets as a preview to static electricity. Now that I have tackled this topic, and that it was such a roaring success, I will do it again, and hopefully do it a little better.


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