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1

what are a matter that continuously changes shape when subjected to shear force (tangential force?

Fluids

2

What are not fluids as they resist shape changes, when their shape is changed they maintain that changed shape

Solid

3

With FLUIDS the stress is proportional to the what?? in r/t to hydrostactics

Rate of change

4

with SOLIDS stress is proportional to the what? in r/t hydrostatics?

change in shape

5

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Are liquids and gasses both fluids?

Yes

6

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what is the big difference between fluids (liq/gas) and solids?

Solids don't change

7

what is perpendicular forces (normal forces)?

force applied perpendicular to surface

8

fluids are matter that respond in one of two ways to normal forces (perpendicular forces).

how do liquids respond?

how do gasses respons?

liquids- resistance to compression , minimal volume changes.

Gasses- compressible and easily expandable

9

equation for force?

F=ma

force= mass X acceleration

10

what are the 3 forces associated with fluids

  1. gravity
  2. pressure
  3. friction

 

11

pressure forces are the result of differences in pressure from one point to another. this is also called the what?

Pressure Gradient

12

friction is proportional to what?

viscosity

13

what is the physical property of a fluid that relates shear stress to rate of strain?

viscosity

14

what is the measure of resistance to flow?

viscosity

15

what is the quanity of a fluid passing a point per unit of time?

 

flow

16

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equation for flow.

give example of how flow is written

F=Q/t

F= mean flow

Q= Quanity

t= time

eg- L/min

mL/hr

etc

17

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what type of flow is smooth flow free of eddies or turbulance, streamlined

Laminar flow

18

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with laminar flow, the flow _______________ is the greatest being about twice the mean flow.

in the center

19

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with laminar flow the flow along the walls of the tube is near what?

zero

20

just to listen for a basic understanding about flow

your on a boat on the sSt. johns river and just cruising along,(lamina the tide is moving and your just cruisin along, thn you get to down town, and the river narrows (by main street bridge) the watr is jst churning little whirl pools and etc. that is now turbulent

21

this a picture of laminar flow notice that the flow in the center is the greatest

22

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laminar (streamlined) flow is described mathmatically by who's law?

Pouiseuille's law

23

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what is the formula for Pouiseuille's law

π=pie 3.14

r= radius

xP= pressure gradient

n= viscosity

l= length

 

24

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With Pouiseuille's law, what 2 thigs are directly proportional

radius4

pressure gradient

25

with Pouiseuille's law F is directly proportional to the fourth power of the radius. what does this mean in laymen terms

flow through a larger bore needle is faster than a small one

26

With Pouiseuille's law F is directly proportional to the hydrostatic pressure gradient, what does this mean in laymen terms?

raising the IV pole increases hydrostatic pressure in fluid delivered to a pt by gravity, flow iincreases proportionally

27

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with Pouiseuille's law what 2 things are inverly proportional to flow

fluid viscosity

length

28

With Pouiseuille's law give an example of how viscosity is inversly proportional to flow

polycythemic pts have higher blood viscosity, flow reduced

Anemic pt's have low viscosity, so flow increased

29

With Pouiseuille's law give an example in laymen terms how length is inversly proportional to flow

reducing the length of a needle inclreases flow from an IV bag

30

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With Pouiseuille's law which factor is the most sensitive to change that will effect flow the most!!!!!

and why?

this will be a test question 

Radius

double the radius= increase in flow x 16

Half the radius= decrease flow t0 1/16th

ex 24=16

14= 1