Units of Measurement/Pressure

thumb|right|250px|This figure shows pressure exerted by particle collisions inside a closed container. The collisions that exert the pressure are highlighted in red. Pressure is the force per unit area applied in the direction perpendicular to a surface. Mathematically, pressure is defined as where: P is pressure F is the component of force perpendicular to the surface A is the area of the surface When a force is constant over an area, the pressure acting on that area is simply It can be given the units of N.m-2. Pressure is a scalar quantity, thus it acts in all directions at any given point. In order for pressure to create a force, the pressure must be integrated over some area.