## what was einstein’s explanation for the photoelectric effect?

Compute the energy of a single photon associated with following electromagnetic waves. Since light’s energy only depends on the frequency, increasing the intensity does nothing to the energy of each photon. However, electron emission was spontaneous no matter how small the intensity of light. Einstein’s Explanation of Photoelectric Effect. Which of the following statements about Einstein’s explanation of the photoelectric effect is not correct? a) High-frequency photons contribute energy above the work function energy to the electron's kinetic energy. Five years later, Einstein published a paper (in the very same issue as his famous paper on relativity) which used Planck's idea of quanta to explain the photoelectric effect's quirks. When light strikes the object it emits electrons. Photons carry momentum and energy from the source of light by which they are emitted. When the energy of incident radiation is higher than the work function of the metal, the electrons receive sufficient energy to eject out of the surface. Both sides had long known how to perform experiments to PROVE that their view was correct. Einstein resolved this problem using Planck’s revolutionary idea that light was a particle. Does Einstein’s explanation of the photoelectric effect invalidate Young’s explanation of the double-slit experiment? The photoelectric effect is an important concept that enables us to clearly understand the quantum nature of light and electrons. Light with energy above a certain point can be used to knock electrons loose, freeing them from a solid metal surface, according to Scientific American. Albert Einstein, a German physicist, is considered one of the greatest scientists ever. Einstein’s Photoelectric Equation- Consider-A photon of energy hν falls on a metal surface. Write Einstein's Photoelectric equation and mention which important features in photoelectric effect can be explained with the help of this equation. The photoelectric effect is an important concept that enables us to clearly understand the quantum nature of light and electrons. Email. The photoelectric effect occurs when light of high enough energy strikes an object. The direct application of the Photoelectric effect is used in photocells and solar cells. Bohr's model of the hydrogen atom. This is the 8th lecture in the series of Atomic and Molecular Physics Sorry!, This page is not available for now to bookmark. Pro Lite, Vedantu How did einsteins explanation of the photoelectric effect lead to the understanding of the dual nature of light? 2) the set up consist of an evacuated glass tube that has a photosensitive metal plate C and another metal plate A as shown. 3-1: Einstein's Explanation of Photoelectric Effect * What Einstein showed was that the photoelectric effect as it had been observed could be explained if individual particles (or quanta) of light were penetrating the metal and knocking electrons loose from atoms. The same case happens with the photoelectrons. Due to the inadequacies of classical physics in explaining the photoelectric effect, in 1905 Albert Einstein further developed upon Planck’s hypothesis to come up with a new ground-breaking theory to explain the photoelectric effect. From the equation, you can know that energy is directly related to frequency, and this also explains the instantaneous nature of electron emissions. According to Einstein’s theory of photoelectric emission, one incident photon of light can eject one photo electron from the metal surface if one photon of suitable light radiation falls on it. Please read our article on Lenard’s observations to understand this part. Your email address will not be published. Stay tuned with BYJU’S to learn more about the photoelectric effect along with engaging video lectures. Einstein's hypothesis and explanation for the photoelectric effect. Therefore, light is made up of packets of energy or quantum of energy. Despite the recognition that Einstein , based on the quantum theory, provided a plausible explanation of the photoelectric effect, textbooks make no effort to clarify that Einstein's explanation of the photoelectric effect was rejected by the scientific community for nearly 20 years (cf. Einstein and the Photoelectric effect So, Planck could ... Planck's explanation of the blackbody spectrum was published in 1900. Because of einsteins explanation of the photoelectric effect, light was shown to behave like a particle or how could it dislodge another particle from a metal atom. The photoelectric effect is a phenomenon in physics.The effect is based on the idea that electromagnetic radiation is made of a series of particles called photons. = hν – hν0. If we hit the ball with other small-sized balls from outside, it can increase its vibration and come out. Pro Lite, CBSE Previous Year Question Paper for Class 10, CBSE Previous Year Question Paper for Class 12. Before Einstein's explanation, the photoelectric effect was a real mystery. What did einsteins explanation about the photoelectric effect state about the nature of light? Photoelectric Effect and Light Quanta The first paper Einstein published in the Miracle Year was titled "On a Heuristic Viewpoint Concerning the Production and Transformation of Light." A particle of light is called a photo. When a photon collides with electrons, it imparts the sum of its energy to it, gaining which the electron ejects out of the surface. Each particle of light, called a photon, collides with an electron and uses some of its energy to dislodge the electron. We show that Einstein’s explanation of photoelectric effect is a causal explanation that has clear epistemological advantages with respect to other rival explanations. So let us try to understand what the explanation behind the Photoelectric effect is. Photoelectric Effect - Einstein's Explanation Prior to Albert Einstein, the field of Physics was in turmoil regarding the Nature of Light. By Elizabeth Howell - Live Science Contributor 25 April 2017. Since energy is dependent on intensity according to wave theory, the low-intensity light should emit electrons after some time so that the electrons can acquire sufficient energy to get emitted. It is calculated experimentally using the stopping potential. (i) Explanation of frequency law: When frequency of incident photon (v), increases, the kinetic energy of emitted electron increases. The photoelectric effect posed a significant challenge to the study of optics in the latter portion of the 1800s. Einstein’s explanation of the photoelectric effect borrowed from his mentor Max Planck. Einstein postulated that a beam of light consists of small bundles of energy, called “quanta" or "photons." a) Electrons have a definite mass. Light: Electromagnetic waves, the electromagnetic spectrum and photons. What would be the best description of Einstein's explanation of the photoelectric effect? = energy required to eject an electron (work function) + Maximum kinetic energy of the electron. This is Einstein's photoelectric equation. The photoelectric effect was one of many experimental results that made up a crisis for classical physics around the turn of the 20th century. Prior to einstein, light was believed ot be a wave. Sep 13, 2016 - The photoelectric effect occurs when matter emits electrons after exposure to electromagnetic radiation. The electrons present inside the atoms of the metal surface gain energy and start vibrating with high frequency, due to the oscillating electric field of the incident light. The energy carried by each particle of light (called quanta or photon) is dependent on the light’s frequency (ν) as shown: Where h = Planck’s constant = 6.6261 × 10-34 Js. (max) = eV0; and putting this in equation (3), we have: Using this equation; the value of 'h' is calculated for the Photoelectric effect. How these experiments led to the idea of light behaving as a particle of energy called a photon. The photoelectric effect was first observed in 1887 by Heinrich Hertz during experiments with a spark-gap generator (the earliest form of radio receiver). It was also one of Einstein’s first successes, and it provides proof of the quantization of light. ● The strength of the photoelectric current depends upon the intensity of incident radiation, and it should be higher than the threshold frequency. Kuhn, Black-Body Theory; Martin J. Klein, "Einstein's First Paper on Quanta," Natural Philosopher 2 (1963): 59-86; Max Jammer, The Conceptual Development of Quantum Mechanics (1966). ● The reverse potential stopping potential was the photo-current stop. To quote him: In simple words, he proposed that in experiments concerning the photoelectric effect, light did not behave like a wave, but rather like a particle, which we refer to as a ‘photon’. Einstein’s photon theory also meets the three objections raised the wave theory for the interpretation of the photoelectric effect. Explaining the experiments on the photoelectric effect. Intensity has no effect on kinetic energy of photoelectrons. ● Incident radiation of higher frequency makes the electrons vibrate faster, thereby increasing the electron emission. Yet, no one back then could explain the causes behind the photoelectric effect. The energy carried by each particle of light (called quanta or photon) is dependent on the light’s frequency (ν) as shown: E = … After continuous research in this field, the explanation for the photoelectric effect was successfully explained by Albert Einstein. If the electron gets energy equal to threshold frequency, its kinetic energy becomes zero after coming out of the surface. T. Kuhn, 1983). The energy carried by each particle of light (called quanta or photon) is dependent on the light’s frequency (ν) as shown: E = hν. The wave-particle duality is the fundamental concept behind quantum mechanics and the reason behind the development of solar cells and electron microscopes. In 1921, Einstein was awarded the Nobel Prize in physics for the discovery of the photoelectric effect. Photoelectric effect. Thus, Einstein explained the Photoelectric effect by using the particle nature of light. 2. i really appreciate for the good notes you have given out, they are easy to understand and to my concern, i am ready to receive more from you, Your email address will not be published. The photoelectric effect. Thus the equation is given as. = hν – hν. b)Ejection of photons occurs when the intensity of light increases beyond a certain minimum. Einstein suggests a solution Planck's explanation of the blackbody spectrum was published in 1900. Notes. The values obtained by this equation are in congruence with actual values, thus proving Einstein's explanation for the Photoelectric effect. Einstein resolved this problem using Planck’s revolutionary idea that light was a particle. Let us consider a ping pong ball inside a bucket. The photo electric effects was one of the first solid examples of the quantization of light. Einstein's idea about light was revolutionary and magnificent. Five years later, Einstein published a paper (in the very same issue as his famous paper on relativity) which used Planck's idea of quanta to explain the photoelectric effect's quirks. So, the kinetic energy of a photoelectron is = (energy imparted by photon) - (energy used to come out of the surface). How to Explain the Work Function of Photoelectric Effect? He suggested that the energy in each quantum of light was equal to the frequency multiplied by a constant (Planck's constant) and that a photon with a frequency over a certain threshold would have sufficient energy to eject a single electron, producing the photoelectric effect. Current depends upon the intensity of light it can increase its vibration and come out perform! 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