What causes snow avalanches? It takes very little to start a snow avalanche. A change in temperature can set it off. Or the pressure from the weight of one skier. Or even someone slamming a car door. Snow avalanches start under the weight of snow...
What is an autopsy? A When a person dies of unknown causes or under suspicious circumstances, usually an autopsy is performed. It means examining the dead body to find out the cause of death. The body is cut open and the internal organs are examined....
How can mixed colours be separated? The method that is used for this purpose is called chromatography. Suppose that a drop of ink is placed in the centre of a piece of paper and some water is sprinkled on top of it. It can be...
How is plastic shaped? Plastic is shaped in many ways. The liquid can be pushed through a nozzle to form sheets, tubes and fibres. Molten plastic may be poured into moulds. More complicated shapes can be made through vacuum farming. In this process, a sheet...
Do robots have uses in industry? Robots are used to handle dangerous chemicals. They are also used in the manufacturing industry. Assembly line manufacturing can involve tedious tasks. Such tasks can be handled by specialist robots which perform only one task. But they still need...
Who are aborigines? Aborigines are the people who have been inhabiting a place before any others arrived there. The word is derived from the Latin aborigine meaning ‘from the beginning’. Roman writers were the first to use the word. The most well-known aborigines in the...
Which snake writes in the sand? In the desert regions of the United States, one can find a snake called the side winding viper. This snake moves along by pushing its body sideways against the sand. When it moves in this manner, it leaves a...
Do fish go to sleep? Fish go to sleep, or rather a state similar to it, with their eyes open. Their eyes remain open as they have no eyelids. Some fish rest while afloat on the water while others rest on the bottom. They may...
Why do astronauts wear spacesuits? Space is not like earth. It is a place that is filled with danger. Spacesuits protect astronauts from harm when they are outside the spacecraft. Also, space is airless. Spacesuits provide astronauts with air to breathe. It also protects them...
Why does the sun have spots on it? The sun’s surface is very hot. In fact, it is 15 times hotter than boiling water. But some parts of the sun’s surface are cooler than other parts. The cooler parts seem darker than the rest of...
