The lowest layer of the atmosphere is called the troposphere. Above it is the second layer, the stratosphere. Around the border between the two layers are strong winds, called jet streams, which blow mostly from west to east at over 160 km/h (100mph). Pilots avoid flying into them, but they often use them as tail winds, so as to increase …

Zero net is the modern strategy to regulate pollution by controlling the use of energy in constructions. The term ‘zero net energy’ is used when the amount of energy utilised by a building is equal to the amount provided by on-site or nearby renewable energy resources. Such buildings are also called zero energy buildings and are gaining popularity in US …

The word is derived from the Greek word xeros, meaning dry. It refers to landscaping which doesn’t require additional water. It uses plants which are suited to the local climate, and practitioners ensure that water doesn’t evaporate or run off. Xeriscaping is also called zeroscaping, drought-tolerant landscaping, smartscaping and waterconserving landscapes. It was developed by the water department of Denver, …

It is the use of non-human animal cells, tissues and organs in human patients. These cells can be implanted or enclosed in a device used outside the body. The tissue is harvested from animals already being butchered. Immune rejection remains the biggest challenge for this. A worrisome element of xenotransplant is the potential for infectious disease from donor animals which …

Wing Loading is the details of the distribution of pressure on an aircraft wing. An aircraft flys by producing Lift by its wings. This lift force depends on the shape of the wing that produces high pressure on the bottom of the wing and low pressure on the top. The center of the lift is usually at the 1/4 chord …

Noise that is produced by combining sounds of different frequencies together is called white noise. Since it contains all frequencies, white noise is used to mask other sounds. When two or three people talk, our brain can distinguish the sound of a particular person. But if a crowd cheers in a stadium, no individual voice can be identified. That’s white …

A wet wing is an aerospace engineering technique where an aircraft’s wing structure is sealed and used as a fuel tank. By eliminating the need for fuel bladders, aircraft can weigh less and offer improved performance. Wet wings are common among civilian designs, from airliners to small general aviation aircraft. Because tanks are an integral part of the structure, they …

Come summer and the entire nation seems to have just one word on its lips – water. Year 2000 saw one of the worst summers recorded in the history of India. The drought in the state of Gujarat and Rajasthan was the worst in decades. Fresh water, they say is a scarce resource. Is it? During the monsoons every year, …

A virus is smaller than the smallest bacteria visible through an ordinary microscope. Viruses can multiply only within the living cells of humans, animals or plants. They are responsible for a wide range of infectious diseases and illnesses. Viruses can be investigated with the help of the electron microscope, and their measurements recorded. The virus responsible for foot and mouth …

It is a technique for encrypting messages consisting of only text and no special characters or numeric digits. It is derived from a much simpler and one of the oldest known encryption systems called Caesar cipher. In the Caeser cipher, the encrypted text is obtained by replacing each character of the original text by a character away from it by …