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, …
Read More »What is virus?
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 …
Read More »What is Vigenere cipher?
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 …
Read More »What is uranium dating?
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 …
Read More »What is Universal Time Coordinated?
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 …
Read More »What is unbreakable glass made of, and is it really unbreakable?
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 …
Read More »What is tongue grafting?
It is a term used in grafting of plants. For the whip and tongue graft, similar cuts are made on the stock and scion. These are made with a single draw of the knife and have a smooth surface so the two can develop a good graft union.
Read More »What is time dilation?
In the theory of special relativity, the slowing down of a clock as determined by an observer who is in relative motion with respect to that clock, is called time dilation. In this phenomenon, a person finds a clock (or other time device) similar or identical to their own, ticking at a slower pace, making the observer believe that time …
Read More »What is thigmotropism?
Thigmotropism is the growth of a plant around a support. Tropism is a phenomena by which a plant, usually climber like money plant and ivy, responds to a stimulus. Stems of the pea plant, for instance, are weak and have coil-like structures called tendrils. When tendrils approach a support (stick), a phytohormone called auxin is released in the side of …
Read More »What is the yuppie flu?
Yuppie flu, which is also called the shirkers’ syndrome, is a term cynically applied to those suffering from chronic fatigue syndrome. Earlier, doctors and others believed symptoms of chronic fatigue such as sleep disorders and other severe problems to be imagined. But now, scientists are linking the yuppie flu to gene mutations.
Read More »