Materials Required:
l Paper straw
l Scissors
l Drinking glass
l Water
Procedure:
- Slit a paper straw across, about 1/3 from one end, making sure you do not slit it all the way through. Bend the straw back like a hinge and insert the short end into a drinking glass.
- Fill the glass with water until the level almost reaches the hinged part of the straw. Now blow hard through the long section of the straw. Water will spray from the glass.
This Is What Happens:
When you blow through the straw, the swiftly moving jet of air reduces the pressure above the hinged opening. The air pressure over the water is now greater, and this pushes water up the short section. When this water hits the stream of air, it is carried away as drops of water. This is the same principle used in many squeeze-type spray bottles. Instead of blowing through a straw, however, you force air through the mechanism with a hand pump.
