Introduction

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Quantum Physics or Quantum Mechanics is the branch of physics, which deals with the study of matter at the scale of atomic or subatomic level.

Illustration of Energy Quanta

Max Planck

In the year 1900, during the study of black body radiation, Max Planck gave the concept of energy quanta (energy in discrete form). In this study he concluded that, energy is absorbed or emitted in discrete form. Later he was awarded the Nobel Prize in Physics in the year 1918, for this finding.

What is meant by the term Quantum?

Quantum is the smallest amount of physical properties which take part in the physical interaction.

Interaction of quantum particle.

Photoelectric Effect
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Photoelectric Effect

“In 1905, Einstein proposed a theory of the photoelectric effect.”

“The photoelectric effect is the emission of electrons when electromagnetic radiation hits a material.”

And the electrons that are emitted from the surface of material are called photoelectrons.

Photoelectric Effect
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Ephoton = hν = KE + W

KEelectron = hν – W

h = Planck’s Constant

ν = Frequency of Light

Ephoton = Energy of Photon

KEelectron = Kinetic Energy of Electron

W = Workfunction = The minimum amount of energy required to emit the electron from the surface of the material.

Bohr Model of an Atom(3D Viewer)

Rutherford Alpha Particle Scattering Experiment (3D Viewer)