Pressure facts for kids

Pressure means how much force something is pushing on something else with. It is expressed as force acting per unit area:

P = F / A

(Pressure = Force divided by Area that force is acting on)

Pressure is directly proportional to force and inversely proportional to area, so the same amount of force applied by a hand will produce less pressure than when applied by something smaller, like a finger.

Pressure is also related to density. If a solid or a fluid is more dense, it has a larger weight, and therefore exerts a larger force, over the same area.

The standard unit of pressure is the Pascal (Pa) named after French physicist Blaise Pascal, who did much work on pressure. 1 pascal = a force of 1 newton per square meter.

Atmospheric pressure is the pressure exerted by oxygen and other molecules (the atmosphere basically) on a body/point/area. Atmospheric pressures is measured using instruments such as the barometer which uses the principles of pressure and vaccum to measure the atmospheric pressure.

Images for kids

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  The effects of an external pressure on an aluminum cylinder

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  Barometer mercury column for pressure measurement

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  Water escapes at high speed from a damaged hydrant that contains water at high pressure

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  Low-pressure chamber in Germany