Fluids

Question 1

What is Hydrostatic pressure?

Answer 1

The pressure fluid molecules in a static column of fluid exert on each other and their surroundings

Question 2

What is osmotic pressure?

Answer 2

minimum pressure which needs to be applied to a solution to prevent the inward flow of its pure solvent across a semipermeable membrane.

Question 3

Write the equation for hydrostatic pressure.

Answer 3

P = pgh where p is the density of the fluid (rho), the acceleration of gravity (g), and the height of fluid above the point

Question 4

Write Bernoulli’s Equation.

Answer 4

Question 5

Describe the relationship between fluid pressure and increased in fluid velocity.

Answer 5

As fluid velocity increases, fluid pressure DECREASES

Question 6

Explain Archimedes’ Principle.

Answer 6

The magnitude of the buoyant force Fb that acts on a floating object is equal to the weight of the fluid displaced by the object

Question 7

Write the equation for buoyant force.

Answer 7

Question 8

Write the equation for pressure.

Answer 8

Question 9

Write the equation for volmetric flow rate.

Answer 9

Question 10

Describe what is the starling equation used for.

Answer 10

used to calculate net fluid filtration and relates membrane permeability (K) to hydrostatic and osmotic pressure within the capillary and interstitial space

Question 11

Write the starling equation.

Answer 11

Question 12

Describe atmospheric pressure.

Answer 12

Pressure that changes with altitude

Question 13

Density

Answer 13

SI= kg/m^3
g/mL
g/cm^3

milliliter and cubic centimeter are same volume

Question 14

Density of water

Answer 14

1 g/cm^3= 1000 kg/m^3

Question 15

Weight of volume of fluid equation

Answer 15

p=density
V=volume
g=acceleration due to gravity

Fb = pVg

common on buoyancy problems

Question 16

Specific gravity

Answer 16

-used to compare density of a fluid to that of pure water at 1 atm and 4 C

SG= p/(1 g/cm^3)

used to determine if an object will sink or float

Question 17

Pressure

Answer 17

-SI unit pascal 1 Pa = 1 N/m^2

P =F/A

Question 18

Conversions of pressure units

Answer 18

1.103 x 10^5 Pa= 760 Torr= 760 mmHg= 1 atm

Question 19

Absolute pressure

Answer 19

-the total pressure that is exerted on an object that is submerged in a fluid

Question 20

Write the absolute pressure equation.

Answer 20

P = Po +pgh

Question 21

Pascal’s principle

Answer 21

an applied pressure to an incompressible fluid will be distributed undiminished throughout the entire volume of the fluid

Question 22

Pascal’s principle equations

Answer 22

for isobaric process W=PΔV=F1/A1(A1d1)=F2/A2(A2d2)–> F1d1=F2d2

the larger the area, the larger the force, although this force will be exerted through a smaller distance

Question 23

Surface tension

Answer 23

causes the liquid to form a thin but strong layer like a “skin” at the liquid’s surface

Question 24

Cohesion

Answer 24

the attractive force that a molecule of liquid feels toward other molecules of the same liquid

Question 25

Adhesion

Answer 25

the attractive force that a molecule of some other substance

Question 26

Viscosity SI unit

Answer 26

Question 27

Write Poiseuille’s Law.

Answer 27

Q=flow rate
P=pressure gradient
n=viscosity of fluid