6 Pressure, Flow, Energy, BP, Vaporization, Heat, & Temp Flashcards Preview

AS - N927 Chem/Physics > 6 Pressure, Flow, Energy, BP, Vaporization, Heat, & Temp > Flashcards

Flashcards in 6 Pressure, Flow, Energy, BP, Vaporization, Heat, & Temp Deck (55)
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1

Force

That which changes or tends to change the state of rest or motion of an object
Push or pull on an object
Vector - direction and magnitude
Type of energy
= Mass (kg) · Acceleration (m/s^2 )
= (kg · m)/s^2
Newtons (N)
(g · cm)/s^2 = Dyne SVR/PVR

2

Work

Measurement of the amount of change a force produces when it acts on an object/body
= Force · Distance (displacement)
= (Mass · Acceleration) · Distance
= kg · (m/s^2 ) · m
= Newton · meters
= (kg 〖· m〗^2 )/s^2 = 1 Joule (J)

3

Total Energy

Kinetic + Potential energy
Internal energy of system = sum potential and kinetic energy in the particles w/in the system
Energy - the currency of force
Capacity to do work (measured in ft lbs)
Measured in Joules

4

Kinetic Energy

= (Mass ·(Velocity)^2 )/2 OR Mass · (Velocity)^2 · 0.5
Energy of motion - energy a mass possesses by being in motion
Measured in Joules

5

Potential Energy

= Mass · 9.8 m/s^2 · Height
= kg · 9.8 m/s^2 · m
= (kg ·〖 m〗^2 )/s^2
= Joule
Energy of height (gravity impact)
*stored for later use*
Example: Rollercoaster
Measured in Joules

6

Power

= Work/Time
= Joules/Seconds
= Watts

7

Reynolds Number

Predicts laminar or turbulent flow
(Inertial Forces)/(Cohesive Forces)
Re < 2,000 Laminar Flow
Re > 4,000 Turbulent Flow (↑ Resistance)
Re 2,000−4,000 Transitional
Re = (velocity ⋅ diameter ⋅ density)/viscosity
Does not consider or predict resistance

8

Resistance/Flow/Pressure

Q = ∆P/R
∆P = Q x R
R = ∆P/Q
Flow - volume gas or liquid passing through cross-sectional area over unit of time (length/seconds) produced by pressure gradient application

9

Pressure

= Force/Area
↑ surface area ↓ pressure
↓ area ↑ pressure
Density directly proportional
↑ density ↑ pressure
Administering drug via 18G vs. 24G IV

10

Dalton's Law

Partial pressure - exerted by single gas component of mixture
P1 + P2 + P3 + PN = Total pressure

11

Atmospheric Pressure Units

760mmHg
760 Torr
14.7 PSI
1,000cmH2O
100 kPa
1 bar
33 ftH2O

12

Pressure at Altitude

Sea level = 1 Atmosphere
10,000ft = 0.66 (2/3) 1 Atmos
20,000 = 0.5 (1/2) 1 Atmos
NOT linear relationship b/w altitude & pressure
60,000 H2O boils 37°C
Underwater:
33ft H2O = 2 Atmos
66ft H2O = 3 Atmos
99ft H2O = 4 Atmos
H2O much more dense than air

13

Acceleration

m/s^2
s^2 = traveling at specific rate m/s per second

14

Rate

m/s
Cruise control - constant mph

15

Pascal's Law

External pressure transmitter equally throughout = homogenous
Pressure transmitted equally therefore able to read via gauge to measure pressure w/in
Not affected by gravity

16

Atmospheric Gas Composition & Pressure

Dry air
N2 79% 594mmHg
O2 21% 159mmHg
(1% trace inert gases)
Water vapor 47mmHg

17

PSIG

Pounds per square inch gauge
Set to read 1 atm (14.7psi or 760mmHg) less than absolute pressure
Indicates usable/useful volume of gas in container
Tank works via negative pressure system, once equilibrates w/ atmosphere then gas will no longer be able to flow out
"Empty" tank not truly empty

18

PSIA

Absolute pounds per square inch
Set to read the TOTAL about gas present in container
Cannot get out unless suction out remainder

19

Absolute Pressure

Gauge pressure + Atmospheric pressure
Total amount gas present in the container

20

Laminar Flow

Stronger intermolecular and cohesive forces = more likely to have laminar flow
↑ IMF ↑ viscosity
VISCOSITY keeps molecules "in-line"
"Sheets" of molecules
Flow α 1/Viscosity
↑ viscosity ↓ flow
Viscosity determinant of gas flow when flow is laminar

21

Turbulent Flow

Velocity, diameter, & density - forces that tend to disrupt cohesive forces therefore molecules move "out of line"
Flow α 1/√Density
↑ density ↓ flow
Density determinant of gas flow when flow is turbulent
Influences probability that interactions b/w fluid molecules will occur - ↑ density ↑ molecules per unit area ↑ chance of molecular collisions ↑ drag ↑ resistance ↓ flow

22

Boiling Point

Temperature at which the vapor pressure of liquid equals ambient pressure
Entirety of liquid enters the gas phase
↑ ambient pressure ↑ BP
Ex: Desflurane ↑ temperature

23

Vaporization

Conversion of volatile liquid to a vapor/gas
Aided by heat

24

Heat

Total kinetic energy of molecules of a substance
Heat energy flows from increased heat to area w/ lower heat energy (hotter to cooler substance) = heat exchange
Energy in form of kinetic energy - resides w/in molecules of the substance
Thermal gradient or conductance
Measurement of substance's ability to conduct (exchange) heat = thermal conductivity

25

Temperature

Thermal state of substance which determines whether it will give heat to another substance or receive heat from another
Average kinetic energy of the molecules of a substance
1L 80°C vs. 3L 80°C water bottle - same temperature
3L will give off more heat
Take 0.5L from each = equal temp and heat

26

Endothermic Process

State of matter change that requires heat input
Chemical example: A + B + Heat = C
Physical change: Ice → Water (add heat)

27

Exothermic Process

State of matter change that required output of heat energy or energy flow out of the system
Giving off heat (output)
Steam → water → ice
Gas → liquid → solid
Heat liberated/released

28

Conduction

Heat transferred from one point to another by direct contact
Patient placed on cold surface

29

Convection

30%
Heat transfer that occurs when a fluid flows over a solid while temperature between the fluid and solid are different
Convection oven or fan blowing cool air

30

Radiation

40%
Transfer of heat through divergence in all directions from a center
Body heat radiates to other objects in the room