The → SI unit of → pressure, that of one → newton per → square → meter. Since 1 Pa is a small pressure, hPa (→ hectopascals) are more widely used. 1 Pa = 10 dyn cm-2, = 1.02 x 10-5 kgf cm-2 = 10-5 bars = 9.87 x 10-6 atm = 7.50 x 10-3 torr (mm Hg).
In honor of Blaise Pascal (1623-1662), French mathematician, physicist, and religious philosopher for his contribution in the study of hydrodynamics and hydrostatics, in particular establishing the principle of the barometer.
Pascal's barrel experiment
âzmâyeš-e celik-e Pascal
Fr.: expérience du tonneau de Pascal
An experiment carried out by Blaise Pascal in 1646 to demonstrate the hydraulic pressure. A long and narrow vertical pipe was connected to the content of a closed wooden barrel already full of water. He poured a small quantity of water into the pipe, whereby the height of the fluid within the pipe sharply increased. Due to the increase in hydrostatic pressure and → Pascal's law, the barrel could leak and even burst.
→ pascal (Pa); M.E. barel, from M.Fr. baril, O.Fr. barril; → experiment
qânun-e pâskâl (#)
Fr.: loi de Pascal
A change in the pressure of an enclosed incompressible fluid is conveyed undiminished to every part of the fluid and to the surfaces of its container.
Named after Blaise Pascal (1623-1662), French mathematician, physicist, and religious philosopher for his contribution in the study of hydrodynamics and hydrostatics, in particular establishing the principle of the barometer.
Fr.: triangle de Pascal
An array of numbers in the shape of a triangle, having a 1 at the top and also at the ends of each row. Each number is obtained by summing the two adjacent numbers to it in the preceding row. Each row is a set of → binomial coefficients. In the expansion of (x + y)n, the coefficients of x and y are given by the n-th row of Pascal's traingle.