Physics

Speed An object is said to be in motion if it changes its position with time, with respect to its surroundings.Speed is defined as the distance moved per unit time, i.e Speed =Distance /Time When we say that an object is at rest or in motion,then this statement is incomplete and meaningless. Basically, rest & … Read more Definition of speed,velocity, gravity, mass, weight, force, impact, work, power and energy

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 Solar system, relative position of Earth with respect to Sun and other planets, movement of earth and moon in solar system, lunar and solar eclipses

Sound is a longitudinal wave, in which the particles oscillate to and fro in the same direction of wave propagation. Sound waves cannot be transmitted through vacuum. The transmission of sound requires at least a medium, which can be solid, liquid, or gas. Newton to derive a relation for the velocity of sound in a gaseous … Read more Concept and nature of sound.Wave length and frequency, infrasonic and Ultrasonic sounds, Sources of Infrasonic sound In nature, Ultrasonic sound characteristics and some applications.

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 System of Units: MKS, CGS and SI