"Flying hot dogs" --were the cries of the children as everyone gathered outside to see the amazing solar bags collect air and then rise as the sun changed the properties of the air inside the bag.
Today the children also presented their inventions as engineers of creatures with plane and solid shapes, and at least two moving parts. Here was the winner of the most impressive creature:
After the students debuted as engineers, they tested their lungs with this next air-blowing experiment.
"The long bag quickly inflates because air from the atmosphere is drawn into the bag from the sides along with the stream of air from your lungs. For you science enthusiasts out there - here's the technical explanation... In 1738, Daniel Bernoulli observed that a fast moving stream of air is surrounded by an area of low atmospheric pressure. In fact, the faster the stream of air moves, the more the air pressure drops around the moving air. When you blow into the bag, higher pressure air in the atmosphere forces its way into the area of low pressure created by the stream of air from your lungs. In other words, air in the atmosphere is drawn into the long bag at the same time that you are blowing into the bag (Steve Spangler).