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Modern Physics

bohr model for hydrogen

 Bohr’s theory of the  hydrogen atom: The Rutherford model of atom and the experimental formula of atomic spectra helped Bohr is solving the problem of atomic structure.In 1913 he proposed a model for the structure of a hydrogen atom based on his experimental observations.  Bohr’s postulates: Neil Bohr based his theory of hydrogen atom on the following three postulates. 1:The ...

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Heisenberg uncertainty principle proof

What is the  uncertainty principle of Heisenberg? Uncertainty principle is defined as:”It is impossible to measure simultaneously both the position and momentum of a microscopic particle with accuracy or certainty.” When we are studying a large moving object say a planet,then we can follow its definition path on which it travels.If we know its initial position and momentum,then we can ...

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Black body radiation

When a body is heated,it emits radiation.The nature of the radiation depends upon the temperature.At low temperature,a body emits radiation which is principally of long wavelengths in the invisible infrared region.At high temperature ,the proportion of shorter wavelength radiation increases. Furthermore,the amount of emitted radiation is different for different wavelengths.It is of interest to see how the energy is distributed ...

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The Photoelectric Effect experiment with animation

What is photoelectric effect? “When light of suitable frequency falls on a metal surface, electrons are emitted from the metal surface.This phenomenon is called photoelectric effect.” The electron emitted in this process are known as photoelectric. Explanation: Experimental Setup: The apparatus used to observe the photoelectric effect is shown in above Figure: It consists of an evacuated glass tube in ...

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