Physics of Anesthesia Flashcards
Temperature vs Heat
Temperature = numerical ranking of hot and cold Heat = the transfer of energy because of a temperature difference
Heat of Fusion
Amount of heat necessary to convert a solid into a liquid at its normal melting point
Heat of Vaporization
Amount of heat necessary to convert a liquid into a gas at its normal boiling point
Critical Temperature
Critical Pressure
Critical Temp - temperature at which a gas can be solidified by pressure only
Critical Pressure - pressure required to solidify a gas at its critical temperature
Specific Heat
Amount of heat (energy) required to raise the temperature of 1 kg of a substance by 1° Centigrade
Transfer of Heat
Conduction - transfer of heat between objects in direct contact with each other
Convection - the up and down movement of gases and liquids caused by heat transfer
Radiation - exchange of heat to an object through electromagnetic waves
Evaporation - dissipation of heat is through skin and respiratory tract
Avogadro’s Law
One mole of an ideal gas at STP (standard temp (0°C) and pressure (1 atm or 760mmHg) occupies a volume of 22.4 L (molar volume)
Graham’s Law
diffusion is directly proportional to molecular weight
Fick’s Law
[(P1-P2) x (area) x (solubility)] ÷ (membrane thickness) x(molecular weight)
Law of Laplace
T=Pr/2
Tension vs Pressure
Pressure - force exerted per area
Tension - the internal force generated by a structure
Poiseuille’s Law
P x π x r4
————– 8 x l x n
Resistance
R=change in P/F
Reynolds number
velocity x density x diameter / viscosity
> 2000 turbulent flow
<2000 laminar flow
Bernoulli Effect
in a tube of varying diameter:
The pressure is highest at the point of greatest diameter and lowest at the point of greatest constriction
Flow is fastest at the point of greatest constriction and slowest at the point of greatest diameter
