Thursday, March 27, 2014

Electrostatics in Action

Do you have a balloon?  Do you have a blanket?  No blanket?  Do you have hair on your head?  If so, you have everything you need for a cool science experiment to do with your kids.  Recently my two daughters each brought home a balloon from a birthday party they attended.  The next morning my oldest was able to stick the balloon to the wall and was very curious by this.  She started asking questions and it turned into a great opportunity to explain the basics of electricity to them.  We started by rubbing a balloon on one of their heads and sticking the balloon to the wall.

Why does the balloon stick to the wall?  Well, the balloon picks up free electrons stripped from your hair (a blanket can work too).  The electrons create a net negative charge on the balloon that attracts to positive charges on the wall.  The electrostatic force holding the balloon to the wall is greater than the downward gravitational force and the balloon sticks.  Slowly, electrons will leak from the balloon and there won't be enough to hold the balloon to the wall and it will fall to the floor.

We also messed around by holding the balloon above my daughters' hair and watching strands of hair reach up toward the balloon.  It led to a lot of laughs and much giggling!  A great way to start a weekend morning!

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