On the other hand, photoelectric effect supported particles nature of light. It was introduced by arthur compton in his explanation of the scattering of photons by electrons a process known as compton scattering. Physics notes class 12 chapter 11 dual nature of radiation and matter cathode rays cathode rays are the stream of fast moving electrons. Thus, every object in motion has a wavelike character. Derivation of the debroglie wave relation stack exchange. We can take the average interparticle spacing in the gas to be approximately vn where v is the volume and n is the number of particles. An alternate and also correct version of this formula is. Mungan, spring 2009 in this brief note i show that the quantum length, equal to the cube root of the quantum volume which in turn is the reciprocal of the quantum concentration, given by.
Chapter 41 wave mechanics national tsing hua university. Matter wave simple english wikipedia, the free encyclopedia. Ncert solutions for class 12 physics chapter in pdf form to free download. Before i derive the equation, it is important to understand the debroglie hypothesis which i am sure. For example, the phase of an em wave at some point is the same as at the lorentz transformed point. But then, the wave nature of electromagnetic radiation is called into question when it is involved in blackbody radiation, photoelectric e. When i conceived the first basic ideas of wave mechanics in 19231924, i was guided by the aim to perform a real physical synthesis, valid for all particles, of the coexistence of the wave and of the corpuscular aspects that einstein had introduced for photons in his. Light and its nature have caused a lot of ink to flow during these last decades. By rearranging the momentum equation stated in the above section, we find a relationship between the wavelength. Derivation of the wave equation most of you have seen the following in your physics 2324 or equivalent sequence. Electron microscope is a common instrument illustrating this fact. Millikan 18681953 devised a method known as oil drop experiment 190614, to determine the charge on the electrons.
Moving double slits, composite mass, and clock synchronization. Download ncert books 202021 and offline apps based on new cbse syllabus 202021. How bohrs model of hydrogen explains atomic emission spectra. Properties of cathode rays i cathode rays are not electromagnetic rays. Dec 04, 2014 the compton wavelength is a quantum mechanical property of a particle. The debroglie wavelength the lorentz transformation had been postulated for electromagnetic waves before einstein developed special relativity. Very low mass particles moving at speed less than that of light behaves like a particle and wave. Computing debroglie wavelengths we usually quote the energy of a particle in terms of its kinetic energy in electron volts, ev or million electron volts, mev. Find the wavelength of an electron moving with a speed of ms1. This equation simply relates the wave character and the particle character of an object. These rays are produced in a discharge tube at a pressure below 0. The reason for this is that particles are usually accelerated to some energy by an electric field.
Compare with compton wavelength of the particle formally speaking, c. Bohr model radii derivation using physics bohr model radii. The same formula gives the momentum of an individual photon associated with a light wave of wavelength. Democritus the atomic theory of matter has a long history, in some ways all the. Quantum physics i, lecture note 4 free online course. An electron and a proton are possessing same amount of k. Instead of using wavelength, its more convenient to deal with wave number itexkitex, which in one dimension is related to wavelength through. This work is licensed under a creative commons attributionnoncommercialsharealike 4. Preface to german translation in the three years between the publication of the original french version, as translated to english below, and a german translation in 19271, the development of physics progressed very rapidly in the way i foresaw, namely, in terms of a fusion of the methods.
Ncert solutions for class 12 physics chapter nuclei pdf. This means that photons, electrons possess both momentum as well as wavelength. Because people thought, anyway light is waves so the surprising thing that would be that matters are waves. What is the debroglie wavelength of a 125 g baseball moving at 28. What happens to a high energy photon after it strikes an electron. Its dual behavior is partly explained by 1doubleslit experiment of thomas young who represents the photons motion as a wave and also by 2the photoelectric effect in which the photon is considered as a particle. A primitive form of this equation was derived by the student in the examination.
The plane matter waves of a free particle moving with speed v has the form. After all, the world would be a mighty strange place if baseballs and ostriches had wavelengths large enough that you could observe their diffraction patterns. But then, the wave nature of electromagnetic radiation is called into question when it is involved in blackbody radiation, photoelectric e ect and such. Dual nature of radiation wave theory of electromagnetic radiation explained the phenomenon of interference, diffraction and polarisation. Sommerfeld refined bohrs theory by incorporating special relativity and the possibility of elliptical orbits. With the addition of two new quantum numbers, the bohrsommerfeld theory accounted for many features of spectra and showed how the periodic table is built up in a systematic way. Important questions for cbse class 12 physics matter wave.
Phase velocity and group velocity for beginners in the first section of this paper i derive the formulas for the phase velocity and group velocity as a function of the total relativistic energy and the momentum of a particle. What is the difference between the debroglie and compton. For a wavelength in nanometers the value in meters must be multiplied by 10 9. These are the same relations we have for the photon, but for. Dual nature of radiation and matter important questions for cbse class 12 physics matter wave. In 1905, einstein suggested that light has a dual character, and behaves both as a particle and a wave.
The same formula gives the momentum of a photon or wavelength translations. Square potential barrier university of texas at austin. His conjecture of dual nature of matter was based on two points. Bohr model energy levels derivation using physics bohr model energy levels. So a free particle with momentum p can be associated to a waveto a plane wave, in factplane wavewith. If an input is given then it can easily show the result for the given number. If the potential energy is independent of time, as we have written above, we can separate eq. The em waves were entirely consistent with relativity. Slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. A proton is accelerated through a potential difference v. The pr esent accepted value of electrical charge is 1.
On substituting the energy on thermal neutron on wavelength of the neutron, we get, on applying the equipartition theorem and the ideal gas equation, we render to the derivation where the lambda is. The relationship is now known to hold for all types of matter. Ncert solutions for class 12 physics chapter 12 atom in pdf form are given below to free download. Quantum physics i, lecture note 4 mit opencourseware free. Ncert solutions for class 12 physics chapter 12 atom pdf. Physics notes class 12 chapter 11 dual nature of radiation. Basing his formula on earlier formulas, he arrived at the equation below. The debroglie equations can be derived from the einsteins famous equation of energymass equivalence and planks theory of quantum radiation.
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