Basic Dive Physics Flashcards
General Gas Law
Boyle, Charles and Gay-Lussac demonstrated that T,V, and P affect a gas in such a way that a change in one factor must be balanced by corresponding change in one or both of the others.
Boyle’s Law
@ a constant T, the absolute P and V of gas are inversely proportional.
Charles/Gay-Lussac Law
@ a constant P, the V of a gas is directly proportional to the change in absolute T.
Dalton’s Law
The total P exerted by a mixture of gases is equal to the sum of the P’s of each of the different gases making up the mixture, c/ each gas acting as if it alone was present and occupied the total V.
Henry’s Law
The amount of any given gas that will dissolve in a liquid @ a given T is directly proportional to the pp of that gas.
Archimede’s Principle
Any object wholly or partly immersed in a fluid is buoyed up by a force equal to the weight of the fluid displaced by the object.
Kinetic Theory of gases
The kinetic energy of any gas @ a given T is the same as the kinetic energy of any other gas @ the same T.
SPAM
Squeezes
POIS
Air consumption
MMP - the amount of pressure your manifold compensates to allow comfortable breathing @ depth (overcoming the ambient pressure).
Partial Pressure:
The ____ is equal to the ____.
whole
sum
Partial Pressure relates to diving (2)
Gas toxicity (N2 narcosis and O2 to)
Re ‘C’ ops, determines TT’s
Natural factors that affect Buoyancy (4)
Air in lungs
Bone structure
Obesity
Leaness
Factors a diver can change to affect buoyancy (5)
add/remove weight put air in BC/LP put air in dry suit put air in lungs thickness of wetsuit
Pressure results in 2 factors
- hydrostatic pressure (wt of H2O)
- atmospheric pressure (wt of Atmosphere)
*the human body must maintain pressure balance because it can only fx correctly c/ little pressure difference between the body and the outside world.
Measurements of Pressure (4)
- Atm pressure = 14.7 psi
- gauge pressure = the difference between the Atm and the pressure being measured.
- ambient pressure = Atm + hydrostatic pressure.
- absolute pressure = total pressure exerted (gauge + Atm).
Numbers and Formulas: - ? wt of Atm = ?Atm = ? few = ? Ata Formulas: - psig - D to Ata - psig to Ata - Ata to pp of gas
- 14.7 psi = 1 Atm = 0 fsw = 1 Ata
- D x .445
- (D + 33) / 33
- (D + 14.7) / 14.7
- Ata x gas %
Wt of H20:
- Seawater
- Fresh water
- 64lbs
- 62.4 lbs
O2 properties (4)
21% of air
metabolized in the body
the only gas the body uses
can be toxic @ Ata 1.3-1.6 or greater.
N2 Properties (4)
79% of air
used to dilute O2
inert gas
cause N2 Narcosis
Inert Gas
Gas not metabolized by the body but dissolves in the tissue.
CO2
byproduct of respiration or metabolized O2.