Posted in Scientific Saturday

Here is a fun science trick you can play on your friends.

You will need:
~ Water
~ A bowl
~ Some Black Pepper
~ A little bit of dish soap

Fill the bowl about halfway with water. Then sprinkle the black pepper over the water (be sure to get it all over, not in just one spot). Put a little bit of the dish soap on the end of your finger... and put your finger down in the middle of the bowl. What in the world? The pepper all flew to the edges of the bowl! Why would that happen?

The reason for this is that the soap spreads rapidly outward in all directions, pushing the pepper. The soap also breaks the surface tension of the water, so after a little bit the pepper will sink to the bottom of the bowl. Oh, and the other thing I have to tell you, lest you get confused, is that the pepper has nothing to do with it. It's just so you can see what's happening.

So here is how you trick your friends... tell this story as you follow the instructions above. But first you must have some soap on your finger (this is a secret, though, so don't let anyone know). There were some children all swimming in a lake, having lots of fun (sprinkle the pepper into the water). All of the sudden, a BEAR came and jumped into the lake! All of the children SCREAMED and ran away (put your finger down into the water)! If you want to do it again you will have to get new water -- if it already has soap in it the trick won't work.

This is a great thing to do with little children. Be forewarned, though, that they will want you to do it again and again! And if you let them know the secret, they will want to do it themselves... again and again! :o)