pressure: Quick Facts

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Facts

Also Known As	bulk stress

Photos

Diagram showing two cylinders, each with gas molecules and a movable piston. The left cylinder (larger volume) has widely spaced molecules and lower pressure, while the right cylinder (smaller volume) shows compressed molecules with higher pressure, illustrating the ideal gas law.

Two U-shaped tubes illustrate water diffusion across a semipermeable membrane. In diagram A, water moves from side 1 to side 2, driven by osmotic pressure and a concentration gradient, with impermeant substances unable to cross the membrane. In diagram B, hydrostatic pressure opposes the movement. Key concepts such as permeability, osmotic pressure, and impermeant membrane are labeled.

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Topics

high-pressure phenomena Osmotic pressure Atmospheric pressure static pressure pressure-gradient force high-pressure device ram pressure brake mean effective pressure internal pressure partial pressure yield point shear stress

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Key People

Robert Boyle

Robert Boyle

Anglo-Irish philosopher and writer

P.W. Bridgman

Percy Williams Bridgman

American physicist

Stephen Hales

Stephen Hales

English scientist

Pyotr Nikolayevich Lebedev

Pyotr Nikolayevich Lebedev

Russian physicist

Carl Bosch

Carl Bosch

German chemist

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Ernst Julius Cohen

Dutch chemist

Italian-born physicist Dr. Enrico Fermi draws a diagram at a blackboard with mathematical equations. circa 1950.

Physics and Natural Law