The aim of this easy experiment is to show the effect of speed on air pressure.
Things Required:
2 books of equal size
1 sheet of notebook paper
1 drinking straw
Ruler
Directions:
Position the books 4 inches (10 cm) apart on a table. Lie the sheet of paper across the space between the books. Place the end of the straw just under the edge of the paper. Blow as hard as you can through the straw.
This Is What Happens:
The paper flops down towards the table when air is blown under it.
Science Behind It:
Air was pushing equally on all sides of the paper before you blew through the straw. As the speed of a flow of air increases, the sideways pressure of the air decreases. Forcing a stream of fast-moving air under the paper reduces the upward pressure on the paper. The air pushing down on the paper is greater than the air pushing up, thus the paper flops down.
