return air flow

When an object moves through a fluid, there will be friction due to the resistance of the material medium. This resistance increases with the velocity of the body as in the case of a rocket and aeroplane. Hence to minimize this friction due to the resistance of the medium, the bodies of aeroplanes..

The air flows smoothly past the wing and the drag is very small. The air strikes the wing at a greater angle and the drag is increased. The air is stirred up, or the air 'burbles' and the drag is very great..

The resources that can be replenished by the environment are called the renewable resources. These are also called the inexhaustible resources. These resources are constantly recycled in the environment like water. This also includes resources like the solar energy, air, plants, animals, ..

Fast cars, boats, planes etc., have a streamlined body. This is to allow air (or water in the case of boats) to easily flow by, without offering much resistanc..

Water potential is regarded as the tendency of water to leave a system. It is often used while explaining the direction in which water flows from one cell to another or from one part of the plant to another e.g., from soil to root, from root to leaves, from leaf to air or ..

Sulphur dioxide is a dangerous air pollutant because of its corrosive properties; it irritates the eyes, nose, and lungs. It is produced by combustion of coal, fuel oil, and gasoline, since these fuels contain sulphur. The sulphur content of a fuel can be reduced by refining, so that less..

Dry air is an insulator. When two charged bodies are brought close, a very strong electric field is created between them. This field can pull out electrons from the air molecules, i.e, ionise the air present between in the gap. As a result there is a flow of..

Sonography is based on ultra sound (frequency above 20 KHz). When high frequency sound waves travel forwards, they continue to move until they make contact with an object. Then a certain amount of the sound bounces back. In medical practice, ultra sound of frequency 1 - 15 MHz in beamed into the h..

Stationary Waves - Stationary or standing waves are formed in a medium when two waves having equal amplitude and frequency moving in opposite directions along the same line, interfere in a confined space. Generally, such waves are formed by the superposition of a forward wave and the reflected wave..