How Airplanes Stay Aloft

A wind bag is like a balloon without any elastic qualities. It’s made out of material that is similar to a plastic grocery bag. It is eight feet long and ten inches in diameter. How many breaths would it take to blow up a bag of this size? 10 . . . 20 . . . 30 . . . more? With a little practice you will be able to blow up the bag in one breath. Try these two exciting activities with your wind bags.