How much pressure is exerted by a person weighing `600 N` when she is standing on her feet? The area of contact between each foot and the floor is...

By definition, pressure is a force (exerted perpendicularly to some surface) divided by an area of that surface. If this force is not constant over a surface, this is the definition of an average pressure.

The Si unit for pressure is `N/m,` which is called Pascal (`Pa`) after the French scientist and philosopher.

In our case, the force is more or less uniform and is given (`600 N`). The area is given also: twice `0.0015 m^2,` or `0.003 m^2.` So the pressure is equal to `600/0.003 = 200,000 (Pa).` This is about twice as much as the standard atmospheric pressure (if you ask "is this a high pressure?").

If she stood on one foot, the pressure would be twice as high.

The answer: the pressure is 200,000 Pa.

Comments

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