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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 ...

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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 ...

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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 ...

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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 ...

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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 ...

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Schrodinger time independent wave equation derivation

time independent schrodinger wave equation

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 ...

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What is difference between electromagnetic waves and matter waves?

Difference between electromagnetic waves and matter waves in tabular form Electromagnetic waves     Matter waves These waves have electric and magnetic fields associated with them. Matter waves have no electric and magnetic fields associated with them. These waves can easily pass through vacuum. These waves cannot pass through vacuum.                     ...

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Planck’s radiation law and quantum theory of radiation

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 ...

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Dual nature of matter and De broglie wavelength

What is dual nature of matter? Our mental views of wave and particles are drawn from familiarity with very large scale objects such as tennis balls and ocean waves.Like paul Davies ,physicist and science writer it is impossible to visualize a wave particle so do not try what then are we to do? Neil Bohr views According to Neil Bohr ...

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Helium (he) Neon (ne) laser working animation

Helium-Neon Laser A helium-neon laser, usually called a HeNe laser, is a small gas laser. Its usual operation wavelength is 632.8 nm, in the red portion of the visible spectrum. Construction:   Working: It is most common type of a lasers used in physics laboratories. Its discharge tube is fitted with 80% helium and 20% neon gas. The neon is ...

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