Definition Planck’s radiation law Rayleigh Jeans law and Wien’s formulae were failed to solve the problem of distribution of spectral radiancy among various wavelengths in cavity radiations because these formulas were based upon the classical theory. Planck’s quantum theory of radiation In 1900,Max Planck gave the new concept about the nature of radiation,called quantum theory of radiation in which planck ...

Read More »## Binding Energy and mass defect

Physically, we define the binding energy as the positive work necessary to dissemble a nucleus into its constituents (nucleons). Equivalently it is the energy liberated when Z proton and N neutrons combine to form a nucleus. For visualization, consider the simplest example of the deutron disintegration. The deutron atom H12 has a mass of 1.014102 a.m.u while the mass of the hydrogen ...

Read More »## Cosmic rays : Definition,uses and effects

The rays which receive on earth from outer space are called cosmic rays.It has been found that extremely penetrating radiations consisting of charged and uncharged particles and photons are reaching the earth. These radiations are called Cosmic Radiations. The sources of these radiations lie beyond the sun or the other stars of our galaxy. The radiations reaching the top of ...

Read More »## State the Pauli Exclusion Principle

According to Pauli Exclusion Principle no two electrons can have samples values of the quantum numbers n, l,ml and ms or they can not have all these quantum numbers similar; at least one of the four numbers which are strictly required to Specify the state of an electron should be different from the quantum numbers which specify the state of an other electron ...

Read More »## Difference and relationship between stress and strain

Stress It is defined as the force applied on unit area to produce change in the shape,volume or length of a body.Mathematically it is expressed as: The SI unit of stress (σ) is newton per square meter (Nm-2),which is given the name pascal (pa). Stress may cause a change in length,volume and shape. Tensile stress When a stress changes the ...

Read More »## Difference between young’s modulus,bulk modulus and shear modulus

Young’s modulus The ratio of tensile stress to tensile strain is called young’s modulus. Young’s modulus formula Bulk modulus For three dimensional deformation,when volume is involved,then the ratio of applied stress to volumetric strain is called Bulk modulus.Mathematically it is expressed as: Bulk modulus formula Where ΔV is the change in original volume V. Shear modulus The ratio of shear stress ...

Read More »## Difference between mechanical and matter waves with examples

Mechanical waves The waves which required any medium for their propagation are called mechanical waves. mechanical waves examples Sound waves Water waves Vibration of string Waves produced on the surface of liquid and solid. Ultrasonic waves Spring waves Slinky waves mechanical waves properties These waves required medium for propagation or to travel. Their speed depend on medium in which it ...

Read More »## Why radio waves diffract around buildings?

Diffraction of radio waves The phenomenon of bending of waves around the corners of an obstacle or opening placed in its path is called diffraction.The phenomenon is found to be prominent when wavelength of the waves is comparable with the size of the obstacle or opening. Radio waves are of large wavelengths and the size of obstacles and openings of ...

Read More »## Schrodinger time dependent wave equation derivation

Schrodinger time independent wave equation derivation Schrodinger time dependent wave equation derivation Consider a particle of mass “m” with velocity “v” and under the influence of potential energy (P.E) which is represented by V(r) .The total energy of the particle is the sum of potential energy (P.E) and kinetic energy (K.E) which is given by: This is ...

Read More »## Schrodinger time independent wave equation derivation

Schrodinger time dependent wave equation What is schrodinger wave equation? In classical mechanics the motion of a body is given by Newton’s second law of motion.But elementary particles like electron,protons and photons possess wave properties as well,therefore another equation instead of Newton’s second law equation ( F=ma) is required for describing their motion.The new equation must take into account wave ...

Read More »