How may breaths are needed to inflate a monster 2.4 meter bag!? 50 or more maybe?

It's almost impossible to believe it can be done with just one breath. But with Bernoulli's principle you can prove it is so!

Use these windbags to demonstrate that fast flowing air creates lower pressure, which pulls extra air into the bag, filling it up with one or two breaths. These bags are so light and strong that even the smallest scientist can demonstrate Bernoulli's principle and the amazing properties of air!

Teach your students how Bernoulli's principle is used by firefighters, hot-air balloon pilots, weather systems and the aviation industry. Science in a bag!

What You Get
4 Plastic Windbags (2.4m x 25 cm)
Instructions & teaching tips

How Does It Work?
The movement of air results from a difference in air pressure. A law of physics known as the Bernoulli principle explains that pressure within a fast moving volume of air deceases with the speed of the air.

This principle is used to explain many phenomena in nature such as how musical instruments produce sound and how baseball pitchers are able to throw a curve ball.

These windbags also work on this principle. When a fast moving stream of air is blown into one end of the tube, surrounding air rushes into the fast moving low-pressure stream increasing the volume of air entering the tube. Thus, one strong blow into the bag picks up enough surrounding air to fill the bag.

Teach
Properties of air molecules
The Bernoulli Effect

WARNING: SUFFOCATION RISK Keep away from small children, and use only under adult supervision.