| A | B |
|---|
| Absolute humidity | The ratio of water vapor in a sample of air to the volume of the sample. |
| Absolute zero | The temperature of - 273.16 or 0 K at which molecular motion vanishes |
| Acceleration: | The rate of change of velocity with respect to time |
| Adiabatic | Any change in which there is no gain or loss of heat |
| Albedo | The fraction of the total light incident on a reflecting surface, especially a celestial body, which is reflected back in all directions |
| Alpha particle | The nucleus of a helium atom (two protons and two neutrons) emitted as radiation from a decaying heavy nucleus |
| Alternating current | The electric current that changes its direction periodically |
| Amorphous: | Solids which have neither definite form nor structure |
| Ampere: | S.I. Unit of electric current, one ampere is the flow of one coulomb of charge per second |
| Angle of repose | The angle of inclination of a plane with the horizontal such that a body placed on the plane is at the verge of sliding |
| Angstrom | A unit of length, 1 = 10-10 m |
| Archimedes principle: | A body immersed in a fluid experiences an apparent loss in weight which is equal to the weight of the fluid displaced by the body |
| The number of protons in an atomic nucleus | The number of protons in an atomic nucleus |
| Avogadro number | The number of molecules in a gram molecular weight of a substance, it is equal to 6.02 x 1023 |
| Avogadro's law: | Under the same conditions of temperature and pressure, equal volumes of all gases contain equal number of molecules. |
| Bernoulli's theorem: | The total energy per unit volume of a non-viscous, incompressible fluid in a streamline flow remains constant |
| Black hole: | The remaining core of a supernova that is so dense that even light cannot escape. |
| Bar | A unit of pressure, equal to 105 Pascals |
| Boyle's law: | For a given mass of a gas at constant temperature, the volume of the gas is inversely proportional to the pressure. |
| Brewster's law | States that the refractive index of a material is equal to the tangent of the polarizing angle for the material |
| Brownian motion | The continuous random motion of solid microscopic particles when suspended in a fluid medium due to the consequence of ongoing bombardment by atoms and molecules. |
| Buoyant force | upward force on an object immersed in fluid. |
| Calorie | A unit of heat, 1 = 4.186 joules. |
| Capacitance | The ratio of charge stored per increase in potential difference. |
| Capacitor | Electrical device used to store charge and energy in the electrical field |
| Centrifugal force | An outward pseudo force acting on a body in circular motion |
| Centripetal force: | The radial force required to keep an object moving in a circular path; it is equal to mv2/r. |
| Conduction | The transfer of heat from a region of higher temperature to a region of lower temperature by increased kinetic energy moving from molecule to molecule. |
| Convection | The transfer of heat by the actual transfer of matter. |
| Doppler Effect: | The apparent change in the frequency of a wave due to relative motion between the source and the observer |
| Diffraction | The bending of light around the corners of an object |
| Dispersion | The splitting of white light into its component colors. |
| Einstein mass energy relation | E = mc2, E is the energy released, m is the mass defect and c is the speed of light |
| Endothermic process: | The process in which heat is absorbed |
| Exothermic process: | The process in which heat is evolved |
| Escape Velocity | The minimum velocity with which an object must be thrown upwards so as to overcome the gravitational pull, it is equal to , where M is the mass of the planet and R is the radius of the planet. |
| Faraday | The electric charge required to liberate gram equivalent of a substance. 1 Faraday = 96485 coulomb/mole |
| Fermat's principle | An electromagnetic wave takes a path that involves the least time when propagating between two points |
| Farad: | The S.I.unit of capacitance, defined as the capacitance of a capacitor that, if charged to 1 C, has a potential difference of 1 V |
| Gamma ray: | A high energy photon |
| Graham's law of diffusion: | The rate of diffusion of a gas is inversely proportional to the square root of its density |
| Ground state: | The lowest energy state of an atom |
| Heisenberg uncertainty principle | It is impossible to have a particle that has an arbitrarily well-defined position and momentum at the same time |
| Hertz | The unit of frequency, also known as cycles per second |
| Half-life: | The time during which half the number of atoms in the element disintegrate |
| Ideal gas Equation: | PV = nRT |
| Inertia: | The property of a body to resist a change in its state of rest or of uniform motion. |
| Infrasonic | Sound waves of frequency less than 20 Hz, below the range of human hearing |
| Isotope | atoms of the same element with same atomic no (no of protons) but different mass no (no of neutrons). |
| Insulators | Materials like wood that are poor conductors of heat or electricity |
