Helium Balloons

Black and white photo of a helium balloon being inflated in the forest.
Credit: National Air and Space Museum, Smithsonian Institution

Helium balloons work by the same law of buoyancy. The helium balloon displaces an amount of air. As long as the helium plus the balloon is lighter than the air it displaces, the balloon will float in the air. This image shows the fully-inflated balloon Explorer II near Rapid City, South Dakota, five minutes before its ascent on its stratospheric research flight on November 11, 1935.

Categories: Gravity & Air