# Please explain pascal's law?

21 Points
15 years ago

Pascal's Law

We have seen that the pressure differences between two points ina liquid at rest depends only on the difference in vertical height between the points. The differences is in fact pgz, where p is the density of the liquid and z is the difference in verical height. Suppose by some means the pressure at one point of the liquid is increased. The pressure at all other points of the liquid must also increase by the same amount because the pressure differences must be the same between two given points. This is the content of Pascal's law which may be stated as follows:

If the pressure is a liquid is changed at a particular point, the change is transmitted to the entire liquid without being diminished in magnitude.

As an example, suppose a flask fitted with a piston is filld with a liquid. Let an external force F be applied on the piston. If the cross c- sectional area of the piston is A, the pressure jus below the piston is increased by F/A. By pascal's law, the pressure at any point B will also increase by the same amount F/A. This is because the pressure at any point B below the piston.