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Here you will play with materials usually not found together - a good thing, as you will see. Rice cereal, plexiglass, and a woolen sweater comprise the task objects. Snaps, pops and a lesson in static electricity are the work products. Emjoy!

• A hand full of crisped rice cereal
• A square foot plate of plexiglass
• Wooden blocks on which to set the plate above the table (1-3 inches high)
• A wool sweater

1. Put the crispy rice cereal on the table surface
2. Next, set the wooden (or non-metallic materials) blocks on the table so that it is a couple of inches above the cereal.
3. Now, rub the top of the plexiglass surface with the wool sweater.
4. What happens to the rice cereal?

What Happened?

By rubbing the wool sweater on the plexiglass, you have generated a net negative charge on the plexiglass surface. This polarizes the cereal below the plexiglass, and the positive charges gather on points nearest to the negatively charged plate. Because opposite charges attract each other, the positively charged crispy rice cereal seems to jump to the negatively charged plexiglass. The cereal’s charge dissipates when it makes contact with the plexiglass, and falls to the table carrying no charge. Then the process of static charge begins again!