Electricity is all around us. It keeps our food cool, the television on and powers our lives. But electricity can be seen in much simpler forms than in refrigerators and entertainment systems.
Try these fun activities at home with your children. By incorporating such simple materials as batteries, wires and fruit, you can help them better understand the basics of how electricity works.
Sprinkle salt and pepper on a plate. Rub a pen against a piece of wool cloth, hard. Pass the pen above the salt and pepper to separate them. Static electricity will attract the pepper to the pen.
Why does this work? Static electricity happens when there is an imbalance between negative and positive charges in objects. You can separate salt from pepper using static
electricity because pepper weighs less than salt. Don’t get too close, because you will get the salt, too.
Make a Circuit
Start with a large rubber band. Wrap it around a 1.5-volt D battery. Use two batteries taped together with duct tape for a brighter light. Attach alligator clips to a bulb holder containing a flashlight bulb, and touch the other end of the wires to the battery. The bulb will light up.
Why does this work? Current flows along the wire from the negative end of the battery to the positive. As you make the circuit, the bulb lights up.
Tip: Materials are available from Radio Shack.
Test It! What Objects Conduct Electricity?
Make a circuit, but this time add an extra test lead.Gather a variety of items, such as coins, plastic spoons, crayons, nails and aluminum foil. Test and separate the items into what conducted electricity and what did not. Try a pencil, too, to test your hypothesis on what you think will conduct electricity.
What works? Most metals are good electrical conductors, and electric current can flow freely. Most nonmetals—also known as insulators—are not. They have an extremely high resistance to the flow of charge going through them.
Make a Tiny Bolt of Lightning
Cut off a corner piece from a Styrofoam tray. Attach the bent piece to an aluminum pie plate to form a handle. Take the rest of the Styrofoam tray and rub it in your hair a lot.
Set the tray upside down on the table. Pick up the pie plate by the handle and drop it on the tray. Very slowly, touch the corner of the tray with the tip of your finger and watch the tiny bolt fly. If you do this in the dark, you will see color.
Why does this work? When you pile up a static electric charge with your hair, the pie pan pulls some of the charge and surges toward you as a spark.
Make a Citrus Battery
Make two slits in a citrus fruit, such as an orange, lemon or grapefruit. Shine a copper coin and a galvanized nail with fine sandpaper. Stick the coin in one slit and the nail into the other. Attach one alligator clip to the end of each wire (a total of two clips).Attach clips to the nail and the coin.
Touch the other ends of the wire to your tongue. If this bothers you, you can use the bulb from the circuit experiment. But kids often love getting a zap.
Why does this work? The zinc from the nail reacts with the acidic citrus juice and loses positive charge, so it has an excess of negative charge. Excess moves along the wire as a current through your tongue to the copper.
For more information, check out the following websites:
Many thanks to Anne Barnes of Kauai Island Utility Cooperative for providing information for this feature.