A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
Adiabatic Process
It is a thermodynamic process in which there is change in temperature, no heat exchange with surroundings & Boyle’s law doesn’t hold good. Adiabatic relation between P, V & T are as follows:
TVγ-1 = const; PVγ = const; P 1-γT γ= const; γ = Cp/Cv
Admittance
It is the term coined by Oliver Heaviside. It is inverse of impedance. In fact, it is vector sum of Conductance and Susceptance. It determines with how much ease an alternating current flows through a complex circuit.
Adsorbate
The gas or liquid that is accumulated over the surface of a liquid or solid is referred to as adsorbate.
Adsorbent
The solid or liquid on whose surface, molecules of other substance are adsorbed.
Adsorption
It is the process of attracting foreign atoms or molecules on to the host liquid or solid substance. Any surface of a solid or liquid exhibit residual forces of attraction normal to surface; hence molecules or atoms impinging on surface are adsorbed.
Aerodynamics
It is branch of fluid dynamics which deals with study of forces and the resulting motion of objects, when air interacts with them.
Aerosol
It is a colloidal suspension of solid or liquid particles in a gas; smoke or fog. Usually aerosol is sealed in a metal container under pressure with an inert gas or other activating agent and released as spray or through nozzle.
After Glow
See Phosphorescence.
Air Break Down
It is dielectric breakdown of air when intense electric field is applied between two electrodes. For instance, dielectric breakdown strength of dry air at STP between spherical electrodes is 33KV/cm.
Air
Mixture of gases with traces of water vapor, etc which makes up earth’s atmosphere. Composition is 78% Nitrogen, 21% Oxygen, 0.03% CO2, 0.00005% Hydrogen, 0.933% Argon, 0.0018% Neon, 0.0005 Helium, 0.0001 Krypton etc.
Albedo
The fraction of the total light incident on a reflecting surface, especially a celestial body, which is reflected back in all directions, is called as Albedo.
Algorithm
A finite set of unambiguous instructions performed in a prescribed sequence to achieve a goal, especially a mathematical rule or procedure used to compute a desired result. Algorithms are basis for most computer programming.
Allobar
It is a form of an element differing in isotopic composition from naturally occurring form.
Allotropy
It is the property of substance to exist in two or more different crystal structures.
Alloy
A metallic
substance that is composed of two or more elements is called as alloy.
Alpha Iron
Name used in
metallurgy for iron or solid solution with iron as main continent with a BCC
(Body centered cubic) structure.
Alpha Particle Spectrum
The line spectrum
formed due to emission of alpha rays from isotopes due to nuclear states
transition.
Alpha Particle
Positively
charged particle identical to Helium nucleus (i.e. two protons and two
neutrons) emitted from radioactive substance having heavy nuclei. They are
typically emitted due to transition in energy states of parent nucleus to form
daughter nucleus.
