Avalanche Multiplication

Phenomenon observed in gas filled detectors as per which when high electric field is applied to anode wire, there occurs rapid multiplication of charges created in primary ionization event near the wire where electric field intensity is high. This process is called avalanche multiplication.

Average Binding Energy

It is obtained by dividing total binding energy of a nucleus by the number of nucleons in nucleus. This energy is a measure of strength of nuclear bonding. The more tightly bound the nucleons; the more stable the nucleus becomes and larger is its binding energy.

Avogadro Number

The number of atoms or molecules in a mole of a substance is called Avogadro’s number. 

Avogadro’s Law

Equal volumes of ideal gases existing under same conditions of temperature and pressure contain equal number of molecules.

Avogadro’s Principle

Whenever a body is fully or partially submerged in a fluid, a buoyant force acts on the body from the surrounding fluid. The force is directed upward and has a magnitude equal to weight of fluid that has been displaced by body.

Axial Chromatic Aberration

For an object at infinity, the difference in focal length of a lens for the red and violet light is called the axial chromatic aberration.

Axis of Precession

The axis about which the direction of rotation of body precesses is called as axis of precession.

Axis of Rotation

When a rigid body undergoes a combined translation and rotational motion, there is at least a point inside or outside the body whose velocity is zero. The body is said to have pure rotation about that point. Then axis passing through that point and perpendicular to plane of rotation is known as axis of rotation.


Vertical and horizontal lines that make up quadrants of coordinate plane are referred to as axis. 

Azimuthal Quantum Number

Azimuthal quantum number is a quantum number, an integer assigned to an atomic orbital. It is also called as “orbital angular momentum quantum number”. It helps in the determination of the orbital angular momentum, which further helps in elucidating the shape of the electron’s orbital. Azimuthal quantum number is the second set of the quantum numbers which determines the quantum state of an electron and assumes integral values from 0 to 1.