What Silver Is? Since ancient times, mining for silver has been carried out. It was a source of wealth for kings in Europe. The King of Spain was delighted at the discovery of America as he would be able to obtain silver from mines in...
What Do You Know About Formation Of Soil? In the absence of a cover over the earth the existence of man would have not been possible. Plants could have not grown. Food for human beings and animals would have not been available. Soil is powdery...
What Is Water Composed Of? Scientists wonder whether life is there on other planets. The existence of life is possible only if there is water. It is an odourless, tasteless, colourless compound and is in major proportion in all living things. Water occurs everywhere in...
What Is Called “Oxygen”? Often we read about something that man “could not live without”. One thing that is absolutely essential to life is oxygen. A human being can not live without oxygen, beyond a few minutes. Oxygen is the most essential and plentiful element...
What Is Fire? ‘Combustion’ is the scientific name given to burning. These are of different types. Oxygen from the air combines with another material that can burn. This reaction produces heat. In case the process is rapid, we see flames or an intense glow and...
What Is The Barrier Of Sound? The name “sound barrier” is actually a wrong way to describe a condition that exists when planes travel at a particular speed. When the speed of sound is attained, a kind of barrier is expected, in actual no barrier...
What Is The Speed Of Sound? We make a sound every day, and with every sound, there is something that vibrated somewhere. Something moves back and forth rapidly. The sound starts with the vibration of an object. Sound has to travel in something which has...
How is a Mirage Caused? Assume a man moving about in the desert and feeling thirsty. He looks off at a distance and sees a lake of clear water, surrounded by trees. He moves on and stumbles to find only hot sand all around him....
What Are X-Rays? Wilhelm Roentgen, a German scientist discovered in the year 1875, X-rays. These rays are also called Roentgen rays. Similar to light rays these are penetrating rays. They differ from light rays in the length of their waves and in their energy. The...
What Is Meant By Radioactivity? In the present time, everybody in the world has heard about radio-activity. There may hardly be an exception. The testing of atom bombs creates radioactivity. This is one of the great problems faced by mankind now. Let us know what...
