The importance of air in our life is very huge as it is the prime cause of life on Earth. Without it life would not be possible as seen on other planets in our Solar system. Hence air is a natural virtue on earth which sustains life. Air is a non-visible form of matter which is free flowing and in gaseous state. The composition of air and its properties are studied widely in physics courses. Air consists of many gases like nitrogen, oxygen, inert gases in major proportions. Besides it also has gases like hydrogen, carbon monoxide, carbon dioxide, sulfur dioxide, nitrous oxide etc.
The following are several other uses of air are many besides its support to living things.
- Air is an essential supply of energy to all living beings: All living beings including plants and animals are dependent on oxygen in the air for generation for living.
- Air is a conducting medium for sound: We can hear sound of speech or cry or noise due to air. etc. only in the presence of air. This is because air is a good conductor of sound. Without air we do-not or cannot hear sound.
- Air supports water cycle: Water cycle is a phenomenon where in water from oceans and seas are evaporated due to sun’s heat and form clouds. These clouds travel on to land surface get cooled by air and shower as rain. This rain water somehow again reaches the sea’s and ocean’s. So air helps in transfer or movement of clouds towards the earth surface and also cools them to shower the rain.
- Air helps in pollination of crops: Plants produce male gametes in the form of pollen grains. These pollens travel from male flower to female flower of same plant or distant plant through air. Thus air helps in cross- pollination in plants.
- Air maintains temperature on the earth surface: During the dry season when there is heavy sunshine, the temperature of earth’s surface rises rapidly but slowly on ocean or sea surface (this is because solid gets heated faster than liquid water). So air which gets heated on earth surface rises up and cold air from sea surface moves on to the earth surface thus minimizing the rise in temperature.
- Air helps in transport: Air transport by flights and helicopters has come into widespread use. Even for birds and insects air is the chief mode of transport. Air transport is quicker than land and water transport. There is less friction so the vehicles travel faster.
- Aerodynamics in landing: Parachutes, hot air balloons are used to safely land from flights in case of need. These flying chute reach the land safely due to buoyancy and pressure of air upwards.
- Air helps in drying (humidity balance): Land when gets wet by rains is dried due to air. The air on the immediate wet surface is very moist. So these moist layers of air are replaced by less moist or dry layers of air. The new dry layer on the surface takes up moisture from wet surface and the cycle continues till the surface dries. Thus air help in drying by maintenance of humidity. Even our clothes when washed gets dried by same manner.
- Air helps in normalizing temperature: A piece of ice melts due to air and hot piece of metal cools due to air. Here air acts as a heat conductor and tries to bring these materials to normal surrounding temperature. Hence the phenomenon of ice melting and metal cooling is seen.
- Air helps reduce friction in tires: Another area where the importance of air is prominent is automobiles. Since the time of automobile emergence their wheels are filled with air inside the rubber tubes of wheels.
- Air minimizes pollution: Environmental issues pollution is a key concern as current life style leads to all sort of pollution. Air helps to minimize air pollution, sound pollution. Without air our big cities would have been vacant due to clogging of polluted gases in the atmosphere. Air blows and spreads the pollution to distance places making towns and cities suitable places to live.
- Wind power (electricity): Flow of air at high speeds is called wind. Wind is used to generate power by installation of wind turbines. These turbines rotate under the influence of wind and generate electric energy. This electric energy is non polluting and can be generated at any place on earth for domestic use.