Units and Measurement

Measurement of any physical quantity involves comparison with a certain basic, arbitrarily chosen, internationally accepted reference standard called unit. The result of a measurement of a physical quantity is expressed by a number (or numerical measure) accompanied by a unit. A unit of measurement is a definite magnitude of a quantity, defined and adopted by … Read more

Earth in Solar system, Motion of the Earth

The Solar System consists of the Sun and its eight main planets, their satellites, asteroids, comets, meteors and other dwarf planets. The Sun is at the one of the two “centers” of The Solar System and the planets revolving around it in elliptical orbits. The sun is in the centre of the solar system. It … Read more