Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Physics B > 3) Fluids In Motion > Flashcards

3) Fluids In Motion Flashcards

You may prefer our related Brainscape-certified flashcards:
Physics 101 flashcards AP® Physics flashcards
1
Q

A fluid is a substance that can continuously deforms under shear stress. What does this mean in normal terms?

A

The substance can flow.

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

What 2 states of matter are fluids?

A

Liquid
Gas

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

What is laminar flow?

A

Where a fluid flows in smoothly changing layers, they are not disturbed by objects.

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

What is turbulent flow?

A

Where a fluid flows in a disorganised random currents, and is very disordered. Obstacles cause more turbulence.

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

Give 3 examples of turbulent flow.

A

Blood flow in arteries
Lava flow
Oil transport in pipelines

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

Give 3 examples of laminar flow.

A

Blood flow in capillaries
Honey being poured
Oil flow through a thin tube

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

What is an eddy?

A

A swirl of fluids

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

Under what 3 conditions do we see laminar flow?

A

Low flow rate
Small area
High viscosity

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

Under what 3 conditions do we see turbulent flow?

A

High flow rate
Large area
Low viscosity

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

How does laminar flow become turbulent flow?

A

Obstacle in the way can interrupt
Change in velocity
Change in area
Change in viscosity

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

How does an aeroplane reduce viscous drag?

A

Streamlined so less friction

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

What is viscosity?

A

How ‘thick’ a liquid is

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

Give examples of very viscous liquids

A

Jam
Honey
Peanut butter

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

What is the term describe low viscous and high viscous fluids according to the concept of young’s modulus?

A

Fluids with low viscosity only require small forces to cause lots of strain

Fluids with high viscosity require large forces to cause small amounts of strain.

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

What is viscosity caused by?

A

By internal friction between layers of flowing fluid due to collisions between particles in the fluid.

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

How does temperature affect viscosity in a liquid?

A

Viscosity decreases as temperature increases because it breaks intermolecular bonds and causes molecules to move faster.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

How does temperature affect viscosity in a gas?

A

Viscosity increases as temperature increases because it causes gas particles to move faster which increases the chance of random collisions. This increases any internal friction, which makes the gas more viscous.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

How does molecular bond strength affect viscosity?

A

Stronger intermolecular bonds mean higher higher viscosity because intermolecular bonds resist the flow of layers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

How does external pressure affect viscosity?

A

Increase in external pressure, increase in viscosity. More collisions between molecules, which means it resists flow.

20
Q

What is viscous drag?

A

The force that acts between layers of fluids and on solid objects the fluid is flowing past

21
Q

What is the best example of viscous drag?

A

Terminal velocity

22
Q

What does newton’s first law state?

A

An object in motion or at rest will continue with the same velocity unless acted on by a net force.

23
Q

How does a parachutist reach terminal velocity?

A

Drag force and weight are equal, so there is no net force on the person. They do not accelerate anymore and have therefore reached terminal velocity.

24
Q

What is a Newtonian fluid?

A

Newtonian fluids maintain constant values for viscosity, and only tend to change with temperature

25
Q

What is a Non-Newtonian fluid?

A

A fluid with highly variable viscosities that change with the size of shear strain (e.g. thickness changes when making it flow)

26
Q

What is the behaviour of a shear-thickening liquid?

A

Viscosity increases immediately when a shear stress is applied

27
Q

What is the behaviour of a shear-thinning liquid?

A

Viscosity decreases immediately when a shear stress is applied

28
Q

What is an example of a shear-thickening liquid?

A

Cornflour and water (oobleck)

29
Q

What is an example of a shear-thinning liquid?

A

Tomato ketchup

30
Q

What are the 5 types of Non-Newtonian fluids?

A

Shear thickening liquid
Shear thinning liquid
Rheopectic liquid
Thixotropic liquid
Bingham plastics

31
Q

What is the behaviour of a rheopectic liquid?

A

Gradually becomes more viscous over time when shaken or agitated

32
Q

Give examples of rheopectic liquid

A

Synovial fluid (joint fluid)
Some printer inks

33
Q

What is the behaviour of a thixotropic liquid?

A

Gradually becomes less viscous over time when shaken or agitated.

34
Q

Give an example of a thixotropic liquid

A

Yoghurt, ketchup

35
Q

What is the behaviour of Bingham plastics?

A

Behaves as a solid at low stresses but behaves as a viscous fluid at high stresses

36
Q

Give an example of Bingham plastics

A

Mayonnaise
Toothpaste
Mud

37
Q

Tomato ketchup can sometimes get stuck in a glass bottle. Describe how shaking the glass bottle makes the ketchup flow quickly

A

Shaking the bottle increases the shear stress on the ketchup, this causes the ketchup viscosity to reduce, particles of ketchup can move across each other more easily, making it flow quicker.

38
Q

Explain why oobleck acts like a solid when jumped on

A

The oobleck becomes more viscous because a sudden shear stress is applied by jumping on it, so the oobleck becomes more rigid.

39
Q

What is the principle of fluid flow?

A

At any point in the pipe, the mass flow rate, must be equal.

40
Q

What is the velocity through a wider pipe and a narrower pipe?

A

The fluid will flow faster through a narrower pipe and slow through a wider pipe.

41
Q

What effect does velocity have on internal pressure?

A

The slower the velocity, collisions are more frequent, this increase the force pushing against the walls of the pipe, which increases internal pressure.

42
Q

What is Bernoulli’s principle?

A

An increase in the speed of a fluid occurs simultaneously with a decrease in internal pressure

43
Q

What is Bernoulli’s principle in terms of energy?

A

The sum of all kinetic, potential and pressure energy in an incompressible liquid is constant along the flow

44
Q

What does potential energy refer to in Bernoulli’s principle?

A

Their position (gravitational)

45
Q

What does kinetic energy refer to in Bernoulli’s principle?

A

Velocity of particles

46
Q

What is the equation for a constant (for a streamline)

A

Pressure energy+ Kinetic energy +Potential energy

Physics B (3 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions