Science & Mathematics Questions & Answers

Movements of plates in the top layers of the Earth’s crust create enormous tension, which sometimes makes long cracks, or faults, in rocks. Continuing tugging movements make blocks of land sink down between roughly parallel sets of faults, forming troughs called rift valleys. The world’s biggest rift valley runs from south-eastern Africa, through East Africa and the Red Sea to …

Most of the movements we make are completely under our control, but some the reflex actions, are not. A reflex action is an automatic response to a stimulus, for example pain, and we cannot control it at all. If you were to touch something very hot, your hand would automatically be pulled away before you had realised that it was …

Red tides are a natural phenomenon caused by high concentration of microscopic algae that are poisonous. The organism produces a toxin that affects the central nervous system of fish, paralyzing them. As a result, dead fish are washed ashore. They can cause human illness and deaths too, following consumption of toxic fish. When red tide algae reproduce in dense concentrations …

The word quasar is short for quasi-stellar object, which means an object that resembles a star. But quasars are not like ordinary stars. Many are thought to be near the edge of the observable universe and moving away from us at nearly the speed of light. But quasars produce intense amounts of light and radio waves, and may be as …

For close to three decades, nucleons (protons and neutrons) were considered to be the ultimate subatomic particles. As scientists delved deeper, they detected shadows of yet another layer of matter inside nucleons. Unable so far to crack open a nucleon and bring out one of these shadowy objects for observation and measurement, they named them quarks. It is believed that …

It is a system of coordinates in Geometry whereby the position of a point, say P, in a plane can be determined with reference to a fixed point called origin, denoted by O, and a predetermined direction represented by a ray OA. The measure of length OP, denoted by r, and the measure of the angle that OP makes with …

You must realize that the Earth provides us with all the raw materials swallowed up by our industries. Many of these material are minerals. The word ‘mineral’ is used to denote any substance obtained by mining. It is clear that the words mine and mineral have similar origins. You might expect that Minerals would be spread throughout the Earth, and …

Nerves are the organs which tell us what is going on in the world outside our bodies, and which take messages about this world to the brain, which translates the messages into feelings. There are four types of nerve in the body. The first is the one which picks up messages like pain, light, cold and heat. The second type …

A mosaic is a picture or pattern made by placing, or fixing, small different-colored pieces of stone or glass side by side. The art was an invention of the Mediterranean peoples and flowered between c. 300-31 B.C. In the Roman period, or about the first five hundred years of the Christian era, mosaics of great beauty ad variety were designed …

Motion capture, or mocap, is a technique for digitally recording movement. Originally used as an analysis tool for biomechanics, mocap is now successfully employed in a wide variety of sectors including games development, advertising, and education. Movement is captured through the placement of sensors on or near each joint of the body. As each joint moves, the positions or angles …