Wave Particle Duality, About, Wave Particle Duality-Light (For CBSE, ICSE, IAS, NET, NRA 2022)

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Wave Particle Duality


  • It possessed by physical entities (such as light and electrons) of both wavelike and particle-like characteristics.
  • Based on the idea that light and all other electromagnetic Radiation may be considered a particle or a wave nature, Louis de Broglie suggested that the same kind of duality must be applicable to matter. He proposed that any particle of matter having momentum (p) Has an associated wavelength () .
  • Based on experimental evidence, German physicist Albert Einstein first showed (1905) that light, which had been considered a form of electromagnetic waves, must also be thought of as particle-like, localized in packets of discrete energy.
  • Early in this century, physicists began to realize the extent to which both models describe the same phenomena. Waves can be described as particles; particles, as waves.
  • The observations of the Compton effect (1922) by American physicist Arthur Holly Compton could be explained only if light had a wave-particle duality.
  • French physicist Louis de Broglie proposed (1924) that electrons and other discrete bits of matter, which until then had been conceived only as material particles, also have wave properties such as wavelength and frequency.
  • Diffraction and interference phenomena reveal a wave- like character in light, but the photoelectric effect shows light to have a particle like character as well. Electrons have mass but can be diffracted like caves.
  • All particles turn out to have a wavelike character described by de Bmplie whelenths.
  • Nature reveals a particle duality and ambiguity uncharacteristic of science. While the meaning of this wave-particle duality remains a subject of intense debate, many physicists now accept the Bohr complement- yarn principle.
  • Two models exclude one another, yet both are necessary for a complete description of nature.

Wave Particle Duality

Wave Particle Duality
  • Publicized early in the debate about whether light was composed of particles or waves, a wave-particle dual nature soon was found to be characteristic of electrons as well.
  • Evidence for the description of light as waves was well established at the turn of the century when the photoelectric effect introduced firm evidence of a particle nature as well.
  • Other side, the particle properties of electrons was well documented when the De Broglie hypothesis and the subsequent experiments by Davisson and Germer established the wave nature of the electron.
  • Observing a light is one of the easiest ways to prove the duality between a particle and a wave. Since light is similar to waves, it is able to diffract, refract, and interface, etc.
  • According to Planck՚s Hypothesis of the Quantum Theory, the energy is emitted in quanta, which are little packets of energy.
  • He states that energy emitted is related to the frequency of the emitted light and this can be considered as Wave Particle Duality definition. According to Planck՚s hypothesis, the quantum energy is related to the frequency by the equation E = hν.

Wave Particle Duality-Light

Wave Particle Duality-Light
  • Albert Einstein՚s theory of photoelectric effect significantly contributed to De Broglie՚s Theory and acted as proof that particles and waves could overlap.
  • The Light can also be observed in the form of a particle called as a photon. When the light is seen on certain objects, the electrons are released.
  • A Certain amount of energy is needed to eliminate an electron from the surface of an object.
  • Thus, when a photon of greater energy than an electron hits a solid, an electron will be emitted.
  • When the electrons are emitted, they also release kinetic energy. According to classical wave theory, the greater is the intensity; greater is the energy. Because the energy of a wave is directly proportional to its amplitude, it was complex for scientists to find high intensity lights that did not affect its overall kinetic energy.
  • The slope of this line is known as Planck՚s Constant, h
  • Though the energy of waves and energy of light does not coincide, we can say that light is a particle that has the property of waves.

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