Brainscape's Knowledge GenomeTM

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


See full index

Fluids > Exam 1 > Flashcards

Exam 1 Flashcards

1
Q

What four quantities have we talked about that all have the same dimensions?

A

Energy, heat, work, torque

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

Of those four, what’s special about torque?

A

Torque is a vector quantity

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

Can gage pressure be negative? Why or why not?

A

yes, Gauge pressure is positive for pressures above atmospheric pressure and negative for pressures below it.

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

Can absolute pressure be negative? Why or why not

A

Absolute pressure can not be negative because it is referenced to zero so that its lowest
absolute pressure can be is 0 psi.

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

Convert [some number] in vacuum pressure to gage pressure

A

Vacuum range is the negative range of gauge pressure. -Vacuum pressure = gauge
pressure.

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

Convert [some number] in vacuum pressure to absolute pressure

A

Absolute pressure = Gage Pressure + Patm = -Vacuum Pressure + Patm

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

What’s momentum?

A

mass x velocity

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

How does force relate to momentum?

A

Force relates to momentum through Newton’s second law of motion in terms of
momentum. The net external force equals the change in momentum of a system divided
by the time over which it changes.

F=Δp/Δt.

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

What are the SI units of density?

A

The SI units of density are 𝑘𝑔/ 𝑚^3

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

What are the SI units of force?

A

kgm/ s^2

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

What’s a Newton

A

is the SI unit derived for a unit of force.

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

example of an object that weight about 1 N

A

an apple

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

Write an equation that relates the number of degrees in a circle to the number of radians
in a circle and show how the dimensions work out.

A

degrees x (2piradians/360 degress) = number of radians

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

SI units of momentum

A

kg m/ s

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

SI units of heat

A

1 Joule = 1 kgm^2 / s^2

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

symbol for specific gravity

A

S.G.

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

What’s viscosity

A

Viscocity is like the stickiness of a fluid, like friction. Causes energy loss.

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

SI units of shear force

A

kg m / s^2

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

What is specific weight

A

Specific weight is the weight per unit volume, 𝛾 = 𝜌𝑔.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

SI units of shear stress

A

kg/ s^2 m = 1 Pascal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

symbol for specific weight

A

gamma, 𝛾

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What’s a joule in terms of kg, m, s

A

kg m^2/ s^2

23
Q

density of water in SI

A

1000 kg/m^3

24
Q

What’s atmospheric pressure in BG (British gravitational)

A

14.7 psi

25
Q

whats the density of air in SI

A

1.2 kg/ m^3

26
Q

atmospheric pressure is SI

A

101 kPa (kN/m^2)

27
Q

what does psi stand for

A

pounds per square inch

28
Q

about how much more dense is water than air

A

water is about 1000 times more dense than air

29
Q

about how much less dense is air than water

A

air is about 1000 times less dense than water

30
Q

In gage pressure, what is the pressure a distance D down into a vat of fluid of density rho

A

Assuming that positive z is downward and the top is z = 0, the pressure at a distance D
down into a vat fluid of density ρ, in gage pressure, is 𝑃 = 𝜌𝑔𝐷.
P = rho g D

31
Q

In absolute pressure, what is the pressure a distance D down into a vat of fluid of density
rho?

A

Assuming that positive z is downward and the top is z = 0, the pressure at a distance D
down into a vat fluid of density ρ, in gage pressure, is 𝑃 = 𝜌𝑔𝐷 + 𝑃𝑎𝑡𝑚.

32
Q

If a tank has height H, what is the gage pressure a distance D up from the bottom of the pool

A

If a tank has height H, the gage pressure a distance D up from the bottom of the pool (z=0 at bottom) is 𝑃 = 𝜌𝑔(𝐻 − 𝐷)

33
Q

If a tank has height H, what is the absolute pressure a distance D up from the bottom of
the pool?

A

If a tank has height H, the absolute pressure a distance D up from the bottom of the pool
(z=0 at bottom) is 𝑃 = 𝜌𝑔(𝐻 − 𝐷) + 𝑃𝑎𝑡𝑚.

34
Q

Write the equation that relates linear velocity to angular velocity and show how the
dimensions work out

A 
𝑣 = 𝜔𝑟
[𝑚/𝑠] = [1/𝑠][𝑚] = [𝑚/𝑠]
35
Q

What is another name for Conservation of Momentum in differential form?

A

Another name for Conservation of Momentum in differential form is Navier-Stokes
equation

36
Q

What is another name for Conservation of Mass in differential form?

A

continuity equation

37
Q

Write an equation to integrate [a function of r and theta] over a circle

A

∫0 to 2pi ∫0 to R 𝑓(𝑟, 𝜃)𝑟 𝑑𝑟𝑑𝜃

38
Q

Write the del operator (nabla)

A

∇ = (𝜕/𝜕x)i +(𝜕/𝜕y)j +(𝜕/𝜕z)k

39
Q

. Given V = a vector, find del dot V, V dot del, V dot del V, the Laplacian of V,

A

doc

40
Q

Can you take the divergence of a scalar?

A

No

41
Q

Show how to derive x = ½ at^2 + v0t + x0 starting from a = a and hold your answer up
to the camera.

A 
𝑎 = 𝑎
𝑣 = ∫ 𝑎𝑑𝑡 = 𝑎𝑡 + 𝑣𝑜

𝑥 = ∫ 𝑣𝑑𝑡 =1/2𝑎𝑡^2 + 𝑣𝑜𝑡 + 𝑥o

42
Q

Consider the pressure at a point 1 foot down into the water in the shallow end of a
swimming pool. How much bigger or smaller is it than the pressure at a point 1 foot
down into the water in the deep end of the pool?

A

The pressure is the same for the pressure at a point 1 foot down into the water in the deep
end of the pool and the pressure at a point 1 foot down at the shallow end of the pool
because pressure only varies with depth, it does not depend on width or length.

43
Q

Now double the area of the pool. How do the pressures at those two points change?

A

Doubling the area of the pool does not change the pressure at those two points because
pressure only varies with depth, it does not depend on width or length

44
Q

Find the normal vectors to [the sides of a triangle shown] and hold your answer up to the
camera.

A

examples in the doc

45
Q

Can the del operator operate on a scalar?

A

The del operator can operate on a scalar. If you take the gradient of a scalar, it yields a
vector

46
Q

Can the del operator operate on a vector?

A

The del operator can operate on a vector. If you take the gradient of a vector, it yields a
tensor.

47
Q

What are the two ways to multiply vectors?

A

cross product and dot product

48
Q

is the gradient a form of vector multiplication

A

no

49
Q

Given a line on a graph with some identifying points, write the equation for that line

A

examples in the doc

50
Q

What are the dimensions of area moment of inertia

A

m^4

𝐼𝑥 = ∫ 𝑦^2𝑑A

51
Q

What are the dimensions of mass moment of inertia

A

kgm^2

𝐼𝑥 = ∫ 𝑦^2 𝜌 𝑑A

52
Q

What is a pascal

A

A pascal is the SI unit derived for quantifying pressure.

Pa= N/m^2 = kg/ ms^2

53
Q

what is specific gravity

A

the ratio of the density of a substance to the density of a standard, usually water for a liquid or solid, and air for a gas.

Fluids (1 decks)

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