Science & Mathematics Questions & Answers

With a little training, we can all swim underwater as freely as a fish. All we need is an aqualung, which consists of portable breathing equipment carried by the diver. The aqualung supplied air naturally as the diver breathes in and out. Wearing froglike fins, aqualung divers can swim quickly with little effort. Before the aqualung was developed, divers had …

The wild goldfish is a very common fish from China, usually green or brown in colour. About a thousands years ago the Chinese noticed that red forms of the wild goldfish occasionally appeared. They started to keep these more attractive forms in ponds and bowls and managed to breed them. Since then goldfishes have always been popular as pets and …

The sun we see everyday is just one of the thousands of stars we see at night. Such a huge collection of stars is called a galaxy. And the stars we see belong to a galaxy called the Milky Way. There are millions of galaxies in the sky, most of whom are hidden from our view. However, there are some …

The animal kingdom is divided into those animals which have backbones, vertebrates, and those animals which do not have backbones, invertebrates. In terms of the numbers of animals which have ever lived throughout the history of the Earth, the invertebrates are much more common. Many invertebrates had external shells made of chalk-like materials to protect them. Others had internal skeletons …

During the sixteenth century, the Portuguese were the principal traders in the East Indies. By 1600, however, their place had been taken by the Dutch who, sailing via the Cape of Good Hope, set up a powerful base on the island of Batavia. Soon their ships were seeking new lands in order to open up more trade. In 1606 a …

Most European speaks one of the Indo-European languages. However, one language, Basque, which is spoken by people in north-eastern Spain and south-eastern France, isn’t related to any other tongue. Its origins are shrouded in mystery and some people have even suggested that it was spoken in the ‘lost continent of Atlantis’. It now seems likely that the ancestors of the …

Although David Livingstone had trained to be a doctor, he decided to go to Africa as a missionary. He sailed for what was then called the Dark Continent on 20 November 1840 and soon found that his work took him into areas that were virtually unknown. In time he crossed the great Kalahari Desert and later reached the bank of …

The first successful English settlement in North America was founded in 1607 by Captain Christopher Newport. It was situated on an island ad named Jamestown in honour of the king, James I, who had given the settlers their Charter. Newport later returned to England and Captain John Smith became the new leader. Early in 1608 he was exploring the Chickahominy …

Saudi Arabia has the largest petroleum reserves in the world. It comprises almost 1/4th (24 %) of the world’s proven total petroleum reserves. Saudi Arabia’s economy is petroleum-based; roughly 75% of budget revenues and 90% of export earnings come from the oil industry. Officially, it has about 260 billion barrels (41,000,000,000 cubic metres) of oil reserves. It has become one …

Bulletproof jackets were being manufactured with ballistic nylon material till the 1970s. In 1965, a compound — poly- parphenyleneterephthalamide – was invented with the brand name Kevlar. This is a liquid polymer which can be spun into fibre and woven into cloth. Kevlar was developed for tyres and, later, for ropes, gaskets and various parts of planes and boats. The …