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Why in the mountains it is hard to breathe?

With the removal from the earth's surface air density decreases. This is because the pressure in the upper layers of the atmosphere is lower than that of the earth.

What is the relationship between air pressure and its density?

The density of a gas is directly proportional to its pressure. The dependence of the density of the air from the pressure equation describes Clapeyron: for an ideal gas

Equation Clapeyron,

where ? - air density, p is the absolute pressure, R is the specific gas constant for dry air (287,058 j?(kg·K)) , T is the absolute temperature in Kelvin.

To calculate the density of the air ? at a certain height above sea level h using the following formula:

The calculation of the density of the air at a given pressurewhere Calculation of air pressure at a given altitude

Here
p0 is the standard atmospheric pressure at sea level (101325 PA);
T0is the standard temperature at sea level (288,15 K);
g - free fall acceleration on the surface of the Earth (9.8 m?sec2);
L - rate of fall of temperature with height in the troposphere (0,0065 K?m);
R is the universal gas constant (8,31447 j?(Mol·K) );
M - molar mass of dry air (0,0289644 kg?Mol).

It is clear and intuitive: the lower layers of air are under the most intense pressure than the top.

What does low blood pressure and reduced air density? This means that such thin air contains fewer molecules, including molecules of oxygen. That is why at high altitude hard to breathe.

By the way...

At 0°C the mass of one cubic meter (1 m3) of air is:

  • at the earth's surface - 1, 293 kilograms;
  • at the altitude of 12 km - 319 grams;
  • at a height of 40 km - 4 grams.

 

 


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Total votes: 114

Your comments:

Dmitry
2014-03-13 16:13:53
Why do you resent the fact that little is written? It is written primarily for children and for adults, who will then explain them clear and accessible language. If you don't know what the atmosphere and the air, something about this in detail can be read in the same Wikipedia. Answers to questions are brief, but very clear and correct. Thank you for the website)
some
2014-03-03 15:19:10
well!!
Gleb
2014-02-18 22:44:56
Little ((
Marinka Marinka
2014-02-16 16:12:19
I just didn't know
Alinka
2013-12-04 20:19:18
In space there is no air means the higher the harder and konchaetsa the air and on the ground plants which contain a special substance and it is easy to breathe
Pavlovets Victoria
2013-09-30 15:59:30
little
Alina
2013-05-24 16:28:20
I understood because in the mountains there are no plants will give the hard disazo and on earth well.
Polina
2013-03-22 13:49:41
I like the CLASS
AAA
2012-12-22 19:44:20
standards
Student)
2012-12-05 19:56:22
Yes a little door to a very

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