1. A

2. B

3. C

4. D

5. E

6. F

7. J

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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.

.

P=

,

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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