```    Where, Strain = strain it has no units                 It states that the pressure applied anywhere
    ∆L =extension measured in metres                        to a body of fluid causes a force to be
    L = original length measured in metres                  transmitted equally in all directions; the
    Hooke"s law states that the force needed to             force acts at right angles to any surface in
extend or compress a spring by some                     contact with the fluid
distance is proportional to that distance.             Attractive forces between molecules of the
    Young"s modulus states that a measure of                same type are called cohesive forces.
elasticity, equal to the ratio of the stress           Attractive forces between molecules of
acting on a substance to the strain                     different types are called adhesive forces.
produced.
Surface Tension ( T )
Pressure (P)
It is the elastic tendency of a fluid surface
    It is defined as force per unit area and it is     which makes it acquire the least surface area
a scalar quantity.                                 possible. Its unit is Nm-1 .
    Its unit is Pascal (pa), which is a Newton
per square meter (N/m2).                                               Force   F
SurfaceTension          
Lenght L
    Pressure of an ideal gas: In an ideal gas,
molecules have no volume and do not
interact. Pressure varies linearly with            Capillary Action or Capillarity
temperature, volume, and quantity
according to the ideal gas law                     It is the ability of a liquid to flow in narrow
nRT                                           spaces without the assistance of, or even in
    P
V                                            opposition to, external forces like gravity.
    Where, P is the absolute pressure of the
gas, n is the amount of substance, T is the        Buoyancy
absolute temperature, V is the volume, R
is the universal gas constant = 8.3145                 It is the ability or tendency to float in
J/mol K                                                 water or other fluid.
    It is also the power of a liquid to keep
Liquid pressure: Pressure in liquid is due to                something afloat is called Buoyancy.
the weight of the liquid acting on the surface
of any objects in the liquid.
P  gh
Where, P = Pressure, h = depth, ρ = density of
liquid, g = Gravitational Field Strength
Atmospheric pressure is the force per unit
area exerted on a surface by the weight of air
above that surface in the atmosphere of Earth
(or that of another planet).
1 atmosphere = 760 torr = 101.3 KPa
The mercury barometer is the standard                   Archimedes" Principle
instrument       for     atmospheric      pressure
measurement in weather reporting.                       It states that the upward buoyant force that is
exerted on a body immersed in a fluid,
Pascal"s Law                                            whether fully or partially submerged, is equal
to the weight of the fluid that the body
displaces.
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