PURPOSE: To demonstrate forces arising from atmospheric air pressure.
DESCRIPTION: About 40 pumps will adequately evacuate the hemispheres, and the vacuum will last about one minute. The hemispheres have a diameter of about 5 inches, thus requiring a force of over 250 pounds to separate them when fully evacuated. A safety restraint prevents the two hemispheres from separating entirely.
REFERENCES: (PIRA 2B30.30)
EQUIPMENT: Magdeburg hemispheres with hand pump and hose.
SETUP TIME: None.
Go back to Lecture-Demonstration Home Page.