- Air is a mixture of gases.It contains mainly nitrogen and oxygen.
- The Troposphere is the atmospheric layer closest to the surface of the earth.It contains the largest percentage of the total mass of the atmosphere.
- The stratosphere is the second major layer of air in the atmosphere.Ozone is formed in stratosphere.
- This layer of calm and clear air is preferred for high speed jet flights because of the absence of air pockets.
- Above stratosphere is Mesosphere, it extends from 50 to 80 km.
- Above mesosphere lies the Ionosphere, which has electrically conducting layers that help in radio communication.
- The Thermosphere is located above the mesosphere .
- The atmospheric pressure is measured by an instrument called a Barometer.
- SI unit of pressure is Pascal. since pascal is a very small unit of pressure, we normally express pressure in kilopascal (kPa)
சனி, 21 மே, 2011
இடுகையிட்டது MANIVANNANRAJA நேரம் முற்பகல் 5:24