Science & Mathematics Questions & Answers

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 …

Uranium dating is one of the ways of determining the age of ancient objects, even one million years old, by measuring how much of the following are present in them: the amount of radioactive isotopes of uranium, and the amount of other materials into which the radioactive isotopes would decompose. These measurements, when combined with knowledge about the initial state …

Universal Time Coordinated (UTC) is a time standard based on International Atomic Time with leap seconds added at irregular intervals to compensate for the Earth’s slowing rotation. A leap second is a positive or negative one-second adjustment to the UTC scale that keeps it close to Mean Solar Time at the Royal Observatory, Greenwich. The difference between UTC and Mean …

The presence of micro cracks on the glass surface (called Griffith’s micro cracks) makes glass breakable under tension or impact. Such micro cracks are unavoidable as the glass surface comes under tension while cooling from a high temperature into various shapes. However, one can increase its impact resistance by various methods, so it can withstand even the impact of a …