Physics Midterm Flashcards
Boyle’s Law
P1V1 = P2V2
Charles’ (Gay Lussac) Law
(V1/T1) = V2/T2
Don’s Law (3rd Gas Law)
P1/T1 = P2/T2
Ideal Gas Law
PV = nRT
STP (standard temp & pressure)
T = 273 K , 0* C
P = 760 mm Hg
RTP (room temp & pressure)
T = 293 K , 20* C
P = 760 mm Hg
BTP (body temp & pressure)
T = 310 K , 37* C
P= 760 mm Hg
Dalton’s Law of Partial Pressure
P(total) = P1 + P2
Therefore, (V(total) / P(total)) = v1/p1 = v2/p2
so, V2/V1 = P2/P1 (or the ratio of partial pressures of volume and partial volume is equal to ratio of total volume and pressure)
Dalton’s Law Example
20.93 kPa O2 + 79.07 kPa N2
100 kPa total
(20.93 % O2 and 79.07% N2)
Amount of O2 L in E cylinder
660 L
PSIg of E cylinder of O2
1900-2000 psi(G)
Amount of N2O L in E cylinder
1600 L
PSIg of E cylinder of N2O
745 psig
van der Waals forces?
(p + (n^2 x a) / V^2) ) (V - nb) = nRT
Water vapor pressure at BTP (37* C)
47 mm Hg
6.3 kPa
Avogadro’s Number
1 mol = 6.02214 x 10^23 molecules
1 mol at STP
22.4 L
1 mol at RTP
24.0 L
1 mol at BTP
25.4 L
Alveolar Oxygen Equation R Value
0.8
Partial pressure of O2 in lungs at room air
Pa O2 = 100 mm Hg
Partial pressure of O2 in lungs on 50% O2
Pa O2 = 300 mm Hg
Partial pressure of O2 in lungs on 100% O2
Pa O2 = 660 mm Hg
V-Q Mismatch in most patients
10%
(10-20%)
Common Pressure Units
1 bar = 1 atm = 14.7 psi = 101.33 kPa = 760 mm Hg
Critical Temperature
Temperature above which liquidification cannot occur however much much pressure is applied
(maximum temp at which liquid can be found)
Critical Pressure
Pressure (vapor pressure) at the critical temperature point
Isotherm
Contains same values of p & v given at same temperature
Critical temp of N2O
36.5* C
A substance that is above its critical temperature at RTP (O2, N2)
A gas
A substance in a gas like state but below its critical temperature at RTP (N2O, CO2, Sevo)
A vapor
How much does 1 L of H2O weigh
1 kg
Filling ratio in US
0.68
Temperature properties
- ) Volume expansion
- ) Conductivity / Resistivity
- ) Emisivity (electromagnetivity)
- ) Index of refraction
Which type of temperature measuring device uses the “Seebeck effect”
Thermocouple
Average temperature under 1 MAC anesthesia
35.5*C
Critical low temp for patient
34* C
What are contributions to heat loss?
Radiation 40%
Convection 30%
Evaporation 20%
Respiration 10% (8% evaporation of water and 2% heating of air)
Define temperature
Temperature is a measurement of the average kinetic energy of the substance being measured
How is heat energy transferred?
Always transferred from an area of higher temp to an area of lower temp
What is the amount of energy in calories to raise the temp of one gram of a substance by one *C
Specific Heat
How many heat calories is required to liquify ice to water?
100 calories
How many heat calories is required to turn liquid into steam?
540 calories
Formula for F and C
F = (9/5)C + 32
How is heat energy transferred?
Conduction, Convection, Radiation
What is primary mode of heat transfer in solids?
Conduction
What is principal method of heat transfer in liquids and gases?
Convection
How does radiation transfer heat energy?
By electromagnetic waves of thermal energy
Stephon - Boltsman Law
E = e(sigma) (T1^4 - T2^4)
(difference between 4th power of each temperature)
What is the principle way of convecting heat to the patients?
Bairhugger
Shape of a dose response curve?
Sigmoidal
Wash in curve?
Build up exponential (1-e^x)
Growth curve?
Positive exponential (e^x)
Normal distribution curve?
Population response curve (bell curve)
Law that describes the balance of forces within / on a sphere?
Leplace’s Law
P = 2T / R
Laminar flow equation?
Hagen-Poiseuille equation
Q = π P r^4 / 8nl
The Fanning equation describes what?
Q^2 = K P 4π^2 r^5 / pl
Turbulent flow
Reynolds number for laminar flow?
NR < 2000
Reynolds number for turbulent flow?
NR > 2000
What is the Continuity Equation?
v1 x a1 = v2 x a2
Change in P = Q x R
Measurement of flow resistance
What is Ohm’s Law?
V = I x R
Law that describes the energy of a fluid?
Bernoulli’s Equation
E = P + þgh + 1/2 pv^2
Law that relates to the action of surfactant?
Leplace’s Law
(p + (n^2 x a) / V^2) ) (V - nb) = nRT
van der Waals forces
