PRESSURE CHAPTER 10

PRESSURE
In fluids, gases and liquids the molecules are free to move. On the way they collide with the walls of container and exert a force on the walls. The force is acting normal to the surface. The force acting normal to surface per unit area is called pressure. It is scalar quantity.  Its dimensional formula is ML⁻¹T⁻². Its unit is Nm⁻² or Pascal (Pa).This unit is in honour of French scientist BLAISE PASCAL. Another common unit of pressure is atmosphere.
The pressure exerted by atmosphere is at sea level is called one atmosphere.(atm)
1 atm=1.013*10⁵Pa
properties of fluid pressure
1)The pressure will be equal at any point in the same horizontal level of a liquid at rest
2)The pressure will be the same in all directions at any point in liquid at റസ്റ്റ്‌
PASCAL'S LAW
Blaise Pascal observed that pressure in a fluid at rest is the same in all directions, if we ignore the gravity. To establish this, consider an elementary volume of liquid which is in the form of right angled prism. Let ABCDEF from the prismatic element of the liquid. The elementary volume is very small so that every pary of it can be considered at the same depth in the liquid.
Let Pₐ  and

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