Physics Ch 4. Fluids Flashcards

1
Q

Fluids

A

Substances that have the ability to flow and conform to the shape of their containers, can exert perpendicular forces but not shear forces, includes liquids and gases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Solids

A

Do not flow and they retain their shape regardless of their containers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Density

A

Mass per unit volume of a substance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Pressure

A

Defined as a measurement of force per unit area, it is exerted by a fluid on the walls of its container in an objects placed in the fluids, it is a scaler quantity and has magnitude only and no direction, the pressure exerted by a gas against the walls of its container will always be perpendicular to the container walls

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Absolute pressure

A

The sum of all pressures at a certain point within a fluid, it is equal to the pressure at the surface of the fluid (usually atmospheric pressure) plus the pressure due to the fluid itself

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Gauge pressure

A

The difference between absolute pressure and atmospheric pressure, and liquids gauge pressure is caused by the weight of liquid above the point of measurement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Pascals principal

A

States that a pressure applied to an incompressible fluid will be distributed and diminished throughout the entire volume of the fluid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Hydraulic machines

A

Create based on the application of pascals principle to generate mechanical advantage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Archimedes principle

A

Burns the buoyant force, when an object is placed in the fluid the fluid generates a buoyant force against the object that is equal to the weight of the fluid displaced by the object

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Buoyant force

A

Force generated by a fluid against an object that is equal to the weight of the fluid displaced by the object, the direction of the buoyant force is always opposite of the direction of gravity, if the maximum buoyant force is larger than the force of gravity that object will float (this will be true of the object is less dense than the fluid it is an), if the maximum buoyant force is more than the force of gravity the object will sink (this will be true if the object is more dense than the fluid it is in)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Cohesive forces

A

Between other molecules of the same fluid, gives rise to surface tension, experienced by fluids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Adhesive forces

A

Between molecules of different materials, experienced by fluids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Fluid dynamics

A

Is a set of principles regarding actively flowing fluids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Viscosity

A

A measurement of a fluids internal friction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Viscous drag

A

A non-conservative force generated by viscosity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Fluid flow

A

Can either be laminar or turbulent, on the MCAT incompressible fluid’s are assumed to have laminar flow and a very low viscosity allowing us to assume conservation of energy

17
Q

Poiseuilles law

A

Relationships determine the rate of laminar flow

18
Q

Continuity equation

A

Statement of the conservation of mass as applied to fluid dynamics

19
Q

Bernoullis equation

A

An expression of conservation of energy for a flowing fluid, this equation state that the sum of the static pressure and the dynamic pressure will be constant between any two points in a closed system

20
Q

Venturi effect

A

For horizontal flow there is an inverse relationship between pressure and speed, and in a close system there is a direct relationship between cross-sectional area and pressure exerted on the walls of the tube

21
Q

Circulatory system fluids

A

Behaves as a close system with non-constant flow, resistance decreases as a total cross-sectional area increases, arterial circulation is primarily motivated by the heart, venous circulation has three times the volume of arterial circulation and is motivated by the skeletal musculature and expansion of the heart, inspiration and expiration create a pressure gradient not only for the respiratory system but for the circular system as well, air at the alveoli has essentially zero speed

22
Q

Weight of a volume of a fluid equation

A

Fg = rhoVg

23
Q

Specific gravity equation

A

SG = rho/1

24
Q

Pressure equation

A

P = F/A

25
Q

Absolute pressure equation

A

P = P0+rhogz

26
Q

Gauge pressure equation

A

Pgauge = P-Patm = (P0+rhogz)-Patm

27
Q

Pascals principle equation

A

P = F1/A1 = F2/A2

F2 = F1(A2/A1)

28
Q

Buoyant force equation

A

Fbouy = rho_fV_fluiddisplacedg = rho_f*V_submergedg

29
Q

Poiseullies law equation

A

Q = pi*r^4DELTAP/8/nu/L

30
Q

Critical speed equation

A

v_c = N_R*nu/rho/D

31
Q

Continuity equation

A

Q = v1A1 = v2A2

32
Q

Bernoullis equation

A

P1+1/2rhov1^1+rhogh1 = P2+1/2rhov2^1+rhogh2