Mat held down by atmospheric pressure.

• C+30+62

diagram for demo

The atmoshperic mat consists of a 10.5” square sheet of Neoprene that lays flat and does not allow air between it and the surface below. Given that atmospheric pressure at sea level is approximately 14.7 lb/in2, the mat theoretically experiences 1620 lbs of pressure. This makes it near impossible to pull the mat off the table by pulling straight up on the hook. However, by peeling the mat off the table, the air creates equal pressure on both sides of the mat allowing it be easily removed. Obviously, due to imperfections in the rubber and the presence of air (particularly under the hook), one requires far less than 1600 pounds of force to lift the sheet. A force transducer or a spring scale can be attached to the hook if you want to show the class how much force is exerted.

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