Rotational Kinematics/Dynamics and Fluids

Question 1

Formula for Angular velocity

Answer 1

ω = (θf - θi) / t

Question 2

Formula for Angular acceleration

Answer 2

α = ω/t

Question 3

How is angular velocity affected by the position of the object

Answer 3

The angular velocity remains the same independently of the objects position

Question 4

How is translational velocity affected by the position of the object

Answer 4

The farther you are from the center the more translational velocity you have

Question 5

I rev is equal to

Answer 5

2π

Question 6

Center of mass formula

Answer 6

Xcm = (m1x1 + m2x2 +…./m1+m2+…)

Question 7

Formula for torque

Answer 7

τ = F*l (perpendicular force x lever arm) or τ = Iα (inertia x angular acceleration)

Question 8

When approaching torque problems, which force do you use

Answer 8

Only use the perpendicular force

Question 9

Formula for Inertia

Answer 9

I = (mr^2)

Question 10

Mass distributed towards the outside

Answer 10

Has more intertia

Question 11

Mass distributed towards the inside

Answer 11

Has less inertia, will reach bottom first (solid)

Question 12

Formula for Angular Momentum

Answer 12

L =Iω

Question 13

Formula for Rotational KE

Answer 13

KE = 1/2(Iω^2)

Question 14

What are the values of force and torque during static equillbirum

Answer 14

F=0

τ = 0

Question 15

How does the gravity of an object relate to the specific gravity of H2O

Answer 15

If an object has 2x the gravity of H2O, then its specific gravity is 2.

If its gravity is 1/2 of H2O then the SG is 1/2 etc.

Question 16

Formula for pressure

Answer 16

P = F/A

Question 17

Units for pressure

Answer 17

1atm = 760 torr = 760mmHg = 100,000Pa

Question 18

Formula for Hydrostatic Pressure

Answer 18

p = ρ(fluid) x g x h(depth)

Question 19

Every 10m depth in H2O equals

Answer 19

1 atm pressure

Question 20

Air can be looked at as a fluid in that

Answer 20

The deeper you go the more the pressure increases

Question 21

When the liquid levels are equal

Answer 21

The pressure inside will equal the pressure in the external environment

Question 22

Formula for Buoyancy Force

Answer 22

Fb = ρgV 
Fb = buoyant force of a liquid acting on an object 
ρ = density of the liquid
g = gravitational acceleration
V = volume of liquid displaced

Question 23

If the object is floating the buoyancy force will equal

Answer 23

The objects weight

Question 24

Formula for % submerged

Answer 24

(Density of object / density of fluid) x 100

Question 25

The difference in height between the fluid is equal to the

Answer 25

Difference between the pressures

Question 26

Formula for Specific Gravity

Answer 26

SG = (density of substance)/(density of H2O)

Question 27

Density of water

Answer 27

1000 kg/m^3

Question 28

In an enclosed structure, fluid force is the same everywhere. This gives rise to the formula

Answer 28

A1d1 = A2d2

Question 29

Formula for a Hydraulic Jack

Answer 29

(F1/A1) / (F2/A2)

Question 30

Laminar Flow

Answer 30

Straight line flow of lines that don’t interact. Once the speed picks up you reach a point of change into turbulent flow where uniformity breaks down.

Question 31

Turbulent flow

Answer 31

Usually we aim to avoid this kind of flow since it lacks uniformity.

Question 32

Flow rate formula

Answer 32

A1v1 = A2v2

Question 33

Within a system the flow rate is always

Answer 33

Constant

Question 34

Bernoulli’s equation

Answer 34

P1+1/2ρv1^2+ρgh1=P2+1/2ρv2^2+ρgh2