The solar balloon is designed to trap solar energy using an inflatable plastic thin-film balloon called a solar concentrator. Half the balloon is transparent. When inflated, sunlight falls on it and focuses on a photovoltaic cell placed at its centre. This design reflects sunlight, producing 400 times the electricity that a solar cell would create without the concentrator and has …

A digital device that detects the signs of charisma and measures them in action, the sociometer is about the size of an iPhone. The wearable gadget is equipped with an infrared sensor and a tiny microphone. It tracks patterns of speech and body movement. The sociometer does not, however, record speech. It was created by computer scientist Alex Pentland and …

In fact, shooting stars are not stars at all. We call them meteors, and scientists believe that they are broken fragments of comets, which still move about in space when the comet itself does so no longer. We see them when they enter out atmosphere because they leave a trail of light behind them, caused by the friction of air …

Seed crystals are tiny single crystals made to dissolve in a solution (or melt) from which larger crystals are drawn either by precipitation, centrifuging or drawing up from a melt. Seeds have the same chemical composition and crystalline structure as that of the larger crystal. Large crystals are grown on a preferred geometer (normally the most densely packed) plane of …

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 …

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 …

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.

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 …

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 …

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.