Show Me Some Science! Air Has Mass

The Little Shop of Physics Crew plays bounce off of a 3.7 meter (approximately 12-foot) beach ball in order to show that air does indeed have mass.

How much does the air weigh?

The air inside the ball has a mass of over 32 kg (70 pounds), which is much more than the mass of the ball itself — only about 7kg (15 pounds)!

How come it’s relatively easy to lift?

When you lift that ball, there is a buoyant force (the same force that makes an object such as a buoy float in the water) and this force cancels out the weight of the air inside the ball; so you only have to lift the weight of the ball, or approximately 7kg (15 pounds). But when it hits, you feel the entire mass of the ball and the air inside–over 40kg (85 pounds)! So it lifts light and hits heavy. Watch how some of our more petite interns bounce right off!