Physics Denise PP Flashcards
(94 cards)
1
Q
The motion of atoms and molecules is described as
A
kinetic energy
2
Q
The two types of internal energy that all matter possesses are ___ energy and ___ energy.
A
potential; kinetic
3
Q
Potential energy is energy of _____
A
position
4
Q
Kinetic energy is energy of _____
A
motion
5
Q
The 3 states of matter are:
A
solid, liquid and gas
6
Q
Solids have more (potential/kinetic) energy
A
potential
7
Q
Solids maintain their shape through what type of attractive forces?
A
Van der Waals forces of attration
8
Q
What type of energy will cause a solid to change shape?
A
kinetic energy (through heat)
9
Q
T/F Liquids can be compressed
A
False
10
Q
Gas molecules have more (potential/kinetic) energy?
A
kinetic
11
Q
T/F When unconfined, gas will expand indefinitely.
A
True
12
Q
Gases have (weak/strong) attractive forces
A
weak
13
Q
T/F All matter is in constant motion
A
True
14
Q
Liquids have more (potential/kinetic) energy
A
potential
15
Q
The parts of a thermometer are:
A
reservoir and capillary tube
16
Q
What is the first law of thermodynamics?
A
Energy can neither be created nor destroyed- it can be transformed
17
Q
4 methods of heat transfer are:
A
conduction, convection, radiation, evaporation/condensation
18
Q
How is heat transferred in conduction?
A
heat flows from the warm object to the cold object until it reaches equilibrium
19
Q
How is heat transferred in convection?
A
through the mixing of fluid molecules at different temperatures via thermal currents
20
Q
T/F Air is a good conductor of heat.
A
False
21
Q
T/F Metals are good conductors of heat.
A
True
22
Q
T/F Conduction and convection require direct contact between two substances.
A
True
23
Q
Infant warmers use what method to transfer heat?
A
radiation
24
Q
Increasing temperature weakens intermolecular forces through what mechanism of action?
A
by increasing molecular vibrations (kinetic energy)
25
What is melting point? (definition)
temperature at which solid becomes a liquid
26
What is latent heat of fusion? (definition)
the energy it takes to convert ice to water without changing the temperature of water (to go from melting point to water)
27
What is latent heat of vaporization? (definition)
the energy it takes to convert water to steam without increasing the temperature of steam (to go from boiling to steam)
28
The measure of an object's ability to perform work is called _____
potential energy
29
T/F When an object cools, it gives up heat.
true
30
Does evaporation occur above or below boiling point?
below boiling point
31
Does vaporization occur above or below boiling point?
above
32
The boiling point of oxygen is (higher/lower) than room temperature
lower
33
In vaporization, liquid molecules have (higher/lower) energy levels?
higher
34
What is absolute humidity (definition)
the actual mass or content of water in a measured volume of air
35
What is relative humidity?
a ratio that compares the absolute humidity that is present to the gas' capacity to hold water vapor
36
Variations in liquid pressure produce an upward supporting force called ____.
buoyancy
37
The temperature at which water vapor condenses back to its liquid form is called
dew point
38
What is the formula for measuring pressure?
Pressure = pounds / square inches
39
What is the formula for measuring liquid pressure?
Liquid pressure = height x density
40
What are the components of a mercury barometer?
scale (calibrated in centimeters and inches), evacuated glass tube, reservoir of mercury)
41
What are the components of an aneroid barometer?
evacuated metal container, fulcrum, scale
42
1 atm = ____ psi
14.7
43
760 mmHg = ____ cmH2O
1034
44
Attractive forces between like molecules is called _____
cohesion
45
Attractive forces between unlike molecules is called ______
adhesion
46
Force opposing fluid flow is called
viscosity
47
T/F Viscosity is directly proportional to the adhesive forces between molecules
False. Viscosity is directly proportional to COHESIVE force
48
The area of liquid gas interface is where you will find this force
surface tension
49
Tension on the wall of a sphere is the product of pressure times the radius of the chamber describes whose law?
LaPlace
50
What is the formula for LaPlace?
P= 4 ST/ r
51
Pascal's principal means that a liquid container's shape will not affect the pressure at the bottom. Pressure of a liquid is determined by what?
height times density
52
Capillary action is defined as ___
the upward movement of liquid into a narrow tube
53
Capillary action occurs as result of the combined actions of ______ forces and surface tension.
adhesive forces
54
Capillary action occurs as a result of the combined actions of adhesive forces and ____
surface tension
55
The pressure that evaporated water particles exert on the surrounding gas molecules is called
water vapor pressure
56
If the weight density of an object is less than 1 g/cm what will happen?
the object will displace a weight of water greater than its own weight and the upward buoyant force will overcome gravity (ie the object will float)
57
The formula for determining buoyancy is:
Buoyancy = density x volume
58
The buoyancy equation is used to measure what liquid property?
specific gravity
59
The ideal molar volume of any gas at STP is _____
22.4 Liters per mole
60
Gas pressure in a liquid is called
gas tension
61
What type of forces oppose fluid flow?
frictional forces
62
What is the equation for determining flow resistance?
Resistance = (P1-P2) /
flow
Resistance equals the pressure difference divided by the flow rate
63
The difference in velocity among concentric layers of flow is called ____
shear rate
64
T/F Surface pressure increases the pressure inside a liquid
true
65
If the radius of a drop of liquid increases, does the pressure within the fluid increase or decrease?
decrease
66
What is the clinical application for LaPlaces law which calculates the pressure inside a liquid bubble?
surfactant in alveoli creates liquid-gas interface. when radius of alveolus decreases, surface tension draws radius even smaller, increasing the pressure of gas inside the alveoli
67
Velocity is a measure of what?
speed (distance per time)
68
Flow is a measure of what?
volume per time
69
What causes liquid to flow opposite of gravity?
capillary action
70
Is heat required for evaporation?
YES! The energy for evaporation comes from either the water or the surrounding air
71
What is the Bernoulli principal?
fluid passing through a tube that meets a constriction experiences a significant pressure drop
72
Fluid that flows through a constriction increases its velocity- what happens to the lateral wall pressure?
it decreases
73
T/F A venturi tube widens just before its nozzle.
False- it widens AFTER the jet or nozzle
74
When the radius of the airway decreases by 1/2, the driving pressure (work of breathing) must increase by ____ to maintain the same flow rate
16 times
75
The inverse relationship between work of breathing and radius of the airway is shown by what law?
Pouiseuille
76
The density of oxygen is is ___ g/L
1.43
77
The density of nitrogen is ___ g/L
1.25
78
The formula for determining the density of a gas is?
molecular gram weight /
| 22.4 L (molar weight)
79
The higher the temperature, the (more/less) soluble a gas will be
less soluble-- higher kinetic energy makes gas leave a solution, not go into it
80
What is the formula for Graham's law?
1/square root of the gas' gram molecular weight
81
What is the molecular weight of oxygen?
32 grams
82
What is the molecular weight of CO2?
44 grams
83
T/F Water vapor pressure is not affected by the percentages of other gases.
True. (It acts equally on all gases in a mixture)
84
Can pressure convert gas to a liquid?
Yes
85
In laminar flow, velocity is fastest where?
in the center of the stream
86
Do high flow rates increase or decrease resistance?
increase
87
Lateral wall pressure drops when a fluid passes through a constriction and velocity increases. What explains this?
Energy can't be lost or gained- so when velocity increased, lateral pressure decreased -- energy was transferred.
88
What are the two ways to increase entrainment of fluid?
increase jet diameter or increase the size of the entrainment port
89
How is humidity measured?
water vapor pressure ( a measure of pressure and temperature), absolute humidity (actual weight/volume of water) and relative humidity (percentage of absolute humidity/saturated capacity)
90
Describe relative humidity
how much water vapor a gas is holding compared to what it can hold (8 oz of water in a 16 oz cup can hold 50% more water)
91
Does absolute humidity change when the temperature changes?
No. Absolute humidity is fixed (it is absolute- get it?)
92
Does saturation capacity change when the temperature changes?
Yes- hot air holds more moisture than cold air
93
Does relative humidity change with temperature?
Yes
94
An increase in temperature will (increase/decrease) relative humidity?
Increase temperature decreases relative humidity
(4 oz water/6 oz container= 66% RH
4 oz water/8 oz container = 50% RH)
