Download - Pressure
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Content
Pressure..
Enthalpy.
Equation of State and Perfect Gas Law.
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Pressure
1. Pascal(Pa)Ex: 1N per 1 Pound per inch - (Psi) atm or Pascal Ex:1atm = 14.696 lb/in2 =1.01325 bar =101.325 kPa
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Pressure
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Pressure
2.
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P=
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P: A: F:
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Pressure
3. ( Absolute pressure) (Local atmospheric pressure ) ( Gauge pressure)
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( Absolute pressure)
(Absolute pressure)
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(Local atmospheric pressure )
(Local atmospheric pressure )
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( Gauge pressure)
( Gauge pressure)
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Pressure
4. Fluid pressure
Fluid pressure is the pressure at some point within a fluid, such as water or air (for more information specifically about liquid pressure.
Applications
Hydraulic brakes Artesian well Blood pressure Hydraulic head Plant cell turgidity Pythagorean cup
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Pressure
Pressure of an ideal gas
Main article: Ideal gas law
In an ideal gas, molecules have no volume and do not interact. Pressure varies linearly with temperature, volume,
and quantity according to the ideal gas law.
where:
p is the absolute pressure of the gas
n is the amount of substance
T is the absolute temperature
V is the volume
R is the ideal gas constant
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Pressure
Vapor pressure
Main article: Vapor pressure
Vapor pressure is the pressure of a vapor in thermodynamic equilibrium with its condensed phases in a closed system. All liquids and solids have a tendency to evaporate into a gaseous form, and all gases have a tendency to condense back to their liquid or solid form.
Liquid pressure
When a person swims under the water, water pressure is felt acting on the person's eardrums. The deeper that person swims, the greater the pressure. The pressure felt is due to the weight of the water above the person.
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Pressure
Formula
where:
p is liquid pressure
g is gravity at the surface of overlaying material
is density of liquid
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Enthalpy
Enthalpy H = Ei + PV
H (kJ) Ei internal energy (kJ) P (kPa) V (m 3 )
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Enthalpy
enthalpy enthalpy
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enthalpy
enthalpy Enthalpy enthalpy
enthalpy , enthalpy ()
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ideal gas PV=nRT P: V: n: R: T:
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Molar form gas
n=
n: mol, m: g, M: g/mol
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PHASE DIAGRAM OF WATER
() superheated vapor
() (saturated vapor)
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PHASE DIAGRAM OF WATER
(Saturation temperature) (saturation pressure)
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