Pair of Industrial Suction Cups with Handles and Release Stubs (Magdeburg Hemispheres)

Pair of Industrial Suction Cups (3.25 inch dia.) with handles and release stubs, also known as Magdeburg Hemisphere, 100 newton (22lbs) separation force. Demonstrates the force of air pressure without a vacuum pump. In this modern variant of a famous 17th-century experiment, student place the edges of two hemisphere cups together and squeeze them, forcing out the air between them. In a tug of war, students try to pull the cups apart, surprisingly difficult task. Each of the 7.5 cm diameter rubber hemisphere has a 2-finger tug handle and 2 release posts.