# particle nature of electromagnetic radiation photoelectric effect

Even higher frequency incoming light (blue) causes ejection of the same number of electrons but with greater speed. Aditya Sardana – Author, Editor, Consultant, Quotes of Aditya Sardana on Homeopathy and Alternative Medicine, Bioinformatics and Charles Darwin – Biological Approach of the New Age, Rationally Coping With High Blood Pressure or Hypertension. Have questions or comments? A photon is a particle of electromagnetic radiation that has zero mass and carries a quantum of energy. He observed the photoelectric effect in which ultraviolet light forces a surface to release electrons when the light hits. For the emission of electrons to take place, the frequency of incident light is required to be greater than a certain minimum value. Contrarily, wave nature is prominent when seen in the field of propagation of light. The phenomenon is studied in condensed matter physics, and solid state and quantum chemistry to draw inferences about the properties of atoms, molecules and solids. Low frequency light (red) is unable to cause ejection of electrons from the metal surface. Photoelectric Effect – Definition: When an electromagnetic radiation of particular frequency and above strikes a given metal, the photons from that radiation knock out electrons from the metal and provide them with a certain kinetic energy.. Watch the recordings here on Youtube! The photoelectric effect is the emission of electrons when electromagnetic radiation, such as light, hits a material. Einstein figured out that a beam of light comprises of small packages of energy known as photons or quanta. The above equation of photoelectric effect also show that greater the work function of a metal or material, the higher the minimum frequency of light required to induce photoelectric effect, i.e., to cause emission of electrons (photoelectrons). The photoelectric effect is applied in devices called photoelectric cells, which are commonly found in everyday items such as a calculator which uses the energy of light to generate electricity. James Clerk Maxwell derived a wave form of the electric and magnetic equations, thus uncovering the wave-like nature of electric and magnetic fields and their symmetry. It is interesting to know that Einstein was awarded the Nobel Prize in Physics 1921 for his work on photoelectric effect. Electrons are emitted from matter that is absorbing energy from electromagnetic radiation, resulting in the photoelectric effect. The photoelectric effect is a phenomenon of emission of electrons from the surface of metals when the light of suitable frequency is incident on the metal surface. Electrons are emitted from matter when light shines on a surface . particle nature of electromagnetic radiation and planck's quantum theory The electromagnetic wave theory of radiation believed in the continuous generation of energy. Still, the particle theory of light got a boost from Albert Einstein in 1905. Consider the $$E = h \nu$$ equation. Thus, putting Kmax = eV0 we get the equation of photoelectric effect: For a given cathode material, work function (ϕ) is constant. Look, up in the sky, it's a particle! The electron gets all of the photon’s energy or none at all. How to check PHP version that a website is using? The LibreTexts libraries are Powered by MindTouch® and are supported by the Department of Education Open Textbook Pilot Project, the UC Davis Office of the Provost, the UC Davis Library, the California State University Affordable Learning Solutions Program, and Merlot. The photoelectric effect cannot be explained by considering light as a wave. 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