|
Pascal's law or the principle of transmission of fluid-pressure (also ''Pascal's Principle''〔http://www.britannica.com/EBchecked/topic/445445/Pascals-principle〕〔https://www.grc.nasa.gov/www/k-12/WindTunnel/Activities/Pascals_principle.html〕〔http://hyperphysics.phy-astr.gsu.edu/hbase/pasc.html〕) is a principle in fluid mechanics that states that pressure exerted anywhere in a confined incompressible fluid is transmitted equally in all directions throughout the fluid such that the pressure variations (initial differences) remain the same. The law was established by French mathematician Blaise Pascal.〔.〕 ==Definition== Pascal's principle is defined as This principle is stated mathematically as: : : is the hydrostatic pressure (given in pascals in the SI system), or the difference in pressure at two points within a fluid column, due to the weight of the fluid; :ρ is the fluid density (in kilograms per cubic meter in the SI system); :g is acceleration due to gravity (normally using the sea level acceleration due to Earth's gravity, in SI in metres per second squared); : is the height of fluid above the point of measurement, or the difference in elevation between the two points within the fluid column (in metres in SI). The intuitive explanation of this formula is that the change in pressure between two elevations is due to the weight of the fluid between the elevations. A more correct interpretation, though, is that the pressure change is caused by the change of potential energy per unit volume of the liquid due to the existence of the gravitational field. Note that the variation with height does not depend on any additional pressures. Therefore, Pascal's law can be interpreted as saying that ''any change in pressure applied'' at any given point of the fluid is transmitted ''undiminished throughout'' the fluid. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Pascal's law」の詳細全文を読む スポンサード リンク
|