It is an emergency shutdown of a nuclear reactor by inserting a large number of negative reactions into the system. It is derived from the WWII usage of the term ‘Safety control rod axe man’ which referred to emergency situations wherein a rope was cut to stop the operations urgently and to limit the damages arising out of continuance of …
Read More »What is a scale model?
A scale model is a representation or copy of an object that is larger or smaller in size. Its size is proportionate to the original size of the object that it represents. The proportion is often shown in some ratio eg 1:10, which means one inch of scale model is equivalent to 10 inches of original object. Very often, the …
Read More »What is a rain shadow?
When winds blow from the sea up high coastal mountain ranges, they shed much of their moisture as rain or snow. However, when they blow down the leeward (sheltered) slopes of the range, they get warmer and pick up moisture, so the leeward side of the range is dry. It is said to be in a rain shadow area.
Read More »What is a rack railway?
Ordinary railway lines usually look as though they are laid on level ground. In reality most stretches of railway track have a slight gradient, so that during a journey of any reasonable length, a train will be running up and down a number of very gradual slopes. However, there is definite limit to the degree of steepness a train can …
Read More »What is a race?
The world race is often wrongly used. For example, the Jews are not a race, but a religious and cultural group, who, in racial terms, are exactly the same as the Nazis who persecuted them. Many scholars say that there is only one race-the human race. However, the human family can be divided into several groups according to such features …
Read More »What is a quadrillion?
Quadrillion is 1,000 trillion. It has a value in which 1 is followed by 15 zeros in Short Scale countries such as UK and USA. In Long Scale countries like some European nations, quadrillion is 1 followed by 24 zeros.
Read More »What is a pulsar?
A supernova leaves behind a tiny object termed a neutron star, far smaller than the Earth. It is the core of the star that exploded. The protons and electrons of its atoms have been squashed together by the force of the supernova, to from the atomic particles known as neutrons. A neutron star is unimaginably dense. It contains the mass …
Read More »What is a prime number?
A prime number is one that cannot be split up by division. Think of 11. Twice six is 12, three fours are 12. But the only number you can divide 11 by is one, and when you have done that you still have 11 left. Prime numbers lie at the very roots of arithmetic, and have always fascinated those concerned …
Read More »What is a persuasive mirror?
It’s a technology that enables people to see how they would look like in the future, based on their habits. Users will have to fill out a questionnaire detailing their lifestyle and upload their images. Based on the information provided, the technology will digitally age the person and show how he/she will appear six months later.
Read More »What is a nuclear meltdown?
A nuclear meltdown is an informal term for a severe nuclear reactor accident that results in core damage from overheating. The term is not officially defined by the International Atomic Energy Agency or by the U.S. Nuclear Regulatory Commission. However, it has been defined to mean the accidental melting of the core of a nuclear reactor, and is in common …
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