Air & basic definitions

Question 1

Composition of air in atmosphere:

Answer 1

Nitrogen : 28%
Oxygen: 21 %
Others: 1% (carbon dioxide, ozone, water vapor, etc)

Question 2

Boyle’s law

Answer 2

**Indirecgtly proportional relationship between pressure and volume
**

In an enclosed area, Sum of pressure and volume remain constant

If pressure increases, volume decreases and vice versa

Question 3

Charles Law

Answer 3

**Directly Proportional Relationship between Temperature and Volume
**
If pressure is constant….

If temperature increases, volume increases and vice versa.

Question 4

Combined gas law

Answer 4

Both Boyle’s and Charle’s law combined:

P1 x V1 = P2 x V2
———- = ———-
T1 T2

The rations remain constant:

The product of Initial Pressure and Initial Volume and New Temperature is equal to
The product of New pressure and New Volume and Initial temperature

Question 5

What are the values of:

Mean Sea Level Temperature
Means Sea Level Pressure
Means Sea Level Density
Lapse Rate

Answer 5

Mean Sea Level Temperature = +15C
Means Sea Level Pressure = 1013 mb
Means Sea Level Density = 1225 grams per cubic meter
Lapse Rate = 1.98C per 1000ft

Question 6

What happens to Air Gas volume percentage at increasing altitude

Answer 6

the percentage remains the same

Question 7

What happens to Oxygen Partial pressure as altitude increases

Answer 7

Oxygen partial pressure reduces as altitude increases

for example:
At mean sea level, the partial pressure of oxygen is 212mb which allows us to take sufficient amount of oxygen in our body

But at 20,000 ft AMSL, partial pressure reduces to 105mb which doesn’t allow us to take sufficient levels of oxygen in our body

Question 8

What happens to pressure as altitude increases

Answer 8

Pressure is reduced as altitude increases

Question 9

At what rate does pressure reduce when altitude increases

Answer 9

1mb per 27 ft above sea level

Ex:

1013mb at sea level
700mb at 10,000ft
500mb at 20,000ft
300mb at 30,000ft