The document discusses compressibility and the bulk modulus of fluids. It defines compressibility as the property of fluids to change in volume with external pressure. Compressibility decreases with increasing pressure as the bulk modulus, defined as the ratio of compressive stress to volumetric strain, increases. The bulk modulus is a measure of a fluid's elasticity and compressibility is its reciprocal. The bulk modulus is not constant and increases with pressure for fluids. Temperature also affects the bulk modulus for liquids, with a decrease as temperature increases. Examples are given for water and air at normal temperature and pressure.

1. Rf
Compressibility and
bulk modulus
Bvc college of engineering
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2. The property by virtue of
which fluid undergo a
change in volume under the
action of external pressure is
known as compressibility. It
decrease with the increase in
pressure of fluid as the
volume modulus increases
with in increasing of
pressure
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3. Elasticity of fluids is
measured in terms
of bulk modulus of
elasticity (K) which is
defined as the ratio
of compressive
stress to volumetric
strain.
Compressibility is
the reciprocal od
bulk modulus of
elasticity
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4. Compressibility=1/K
NOTE POINTS
* The bulk modulus of elasticity (k)of a
fluid is not constant but it increases in
increased in pressure
* The bulk modulus of elasticity (K)
of the the fluid is affected by the
temperature of the fluid in the case of
liquids there is a decrease of K with
increase of temperature
* At NTP
K water = 2.07×10^6 kN/m^2
Kair. = 101.3 kN/m^2
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5. SURFACE TENSION
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6. SURFACE TENSION
Surface tension is caused by the force of cohesion at the free
surface. A liquid molecule in the interior of the liquid mass is
surrounded by other molecule above the surface to balance the
force of the molecule above it.
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7. Some important examples of phenomenon of
surface tension
Rain drops
Rise of sap in a tree
Bird can drink water from ponds
Collection of dust particles on the water surface
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8. Akash.G