Materials Required:
l Sheet of typing paper
Procedure:
- Hold an 8½ – by 11-inch sheet of typing paper high above your head. Use both hands to grasp the paper. Let go. The paper will scoot in various directions and probably turn over.
- Now make two folds in the long side of the paper, first, 1 inch inward, then, 1 inch again.
- Hold the paper over your head, but make sure that the folded edge is at the front, and on the underside, of the sheet. Gently push the paper as you release your grip. The paper will not turn over and will glide for some distance before falling to the ground.
This Is What Happens:
As the plain sheet of paper falls, the force of the rushing air over it causes differences in air pressure over different parts of the paper. The front end tilts up, and the paper may move in a topsy-turvy fashion. However, by folding the edge, you increase the weight that is at the front, and this weight balances the upward force of air, causing the paper to glide smoothly without flipping over. Airplane wings are shaped like this also–they are a little bit heavier in front than they are in the rear–which helps make the ride a smooth one.
