“Relax, we won’t flood your facebook ), de Broglie wavelength (λ):- λ = h/mv = h/√(2mE) = h/√(2meV). Here h is the Planck’s constant and f is the frequency. Therefore, radioactive decay constant is defined as the reciprocal of time in which the number of atoms of radioactive sample is reduced to N0/e. K�"xPd�>JpaPDl�JpA'aQT��U����FE�V�:���)" % ���`����Cq+��� 3��3}�s�ݾ����} �� 6����. 4 SUMMER 2019, ARTEM G. ABANOV,MODERN PHYSICS. ? Half-life (T1/2):- Half-life of a radioactive substance is defined as the time during which the number of atoms of the substance are reduced to half their original value. Old Dominion University. 0000006736 00000 n ?A fusion reaction is one in which two lighter nuclei get fused together to form a heavy nucleus. All the material they contain -- except for chapter 0 -- is examinable, whether or not it has been explicitly discussed in class. Therefore, radioactive decay constant is defined as the reciprocal of time in which the number of atoms of radioactive sample is reduced to N, Radioactivity of a substance is said to be 1 Rutherford if its atoms disintegrate at the rate of 10. number, Please choose the valid Lorenzforce. (d) The emission of electrons stops below a certain minimum frequency known as threshold frequency. 1729 flp lecture photos. (f) Rate of disintegration of the radioactive substance, at any instant, is directly proportional to the number of atoms present at that instant. (a) Stopping potentialdepends upon thefrequency of light. Lorenzforce. Lorentz transformations. (b) Electrons are capable of revolving only in certain fixed orbits, called stationary orbits or permitted orbits. If we use atomic mass instead of nuclear masses, then, Binding Energy, B = [ZmH + (A-Z)mn – Mat] c2. Density of nucleus = mass/volume = A/(4/3 πR. H�l�yTSW��{/$! Binding Energy = (ΔM) c2 = [Zmp + (A-Z)mn – M] c2. All lecture notes with drawings., All lecture notes with drawings., All lecture notes with drawings. FAQ's | Isobars:- Nuclei having same mass number A but different atomic number Z are called isobars. (d) Current depends upon the intensity of incident light. Revision Notes on Modern Physics Atomic Physics. %PDF-1.3 %���� All the material they contain is examinable, whether or not it has been explicitly discussed in class. Course Info . e/m = v/rB. (c) While revolving permitted orbit an electron possesses angular momentum L (= mvr) which is an integral multiple of h/2π. The lecture notes constitute the main reference for the Modern Physics part of the course. Tav = sum of lives of all atoms / total number of atoms. (c) The stopping potential and hence the maximum velocity of the electrons depends upon the frequency of incident light and is independent of its frequency. For S.I system (k=1/4πε0), RH = (1/8ε02) (me4/ch3), (a) For Lyman series:- 1/λ = R [1– 1/n2], n = 2,3,4…..∞, (b) For Balmer series:- 1/λ = R [1/22 – 1/n2], n =3,4,5…..∞, (c) For Paschen series:-1/λ = R [1/32 – 1/n2], n =4,5,6…..∞, (d) For Brackett series:-1/λ = R [1/42 – 1/n2], n =5,6,7…..∞, (e) P-fund series:-1/λ = R [1/52 – 1/n2], n =6,7,8…..∞, For the first excited state, n=2, W2 =W1/4 = (-13.6/4) eV = -3.4 eV, For the second excited state, n=3, W3 =W1/9 = (-13.6/9) eV = -1.51 eV, Similarly, for other excited states, W4 = -0.85 eV and W5 = -0.54 eV, Number of emission lines from excited state:-n = n(n-1)/2. Contact Us | Lecture Notes: Lecture notes are in pdf (portable document format) Download the free Adobe Acrobat Reader: Lectures notes for Fall 2006 are bellow: Lecture 1: Wed. Sep 6. Beta decay:- It is the process in which a parent nucleus decays into the daughter nucleus by ejecting an electron. Pre-Newtonian physics . Here Mat is the mass of the atom  and mH is the mass of the hydrogen atom. It decays in to any other lower state or ground state by emitting γ-rays. 0000049800 00000 n Careers | This is achieved by passing them through moderators. Radioactivity:- The phenomenon by virtue of which substance, spontaneously, disintegrate by emitting certain radiations is called radioactivity. All the material they contain is examinable, whether or not it has been explicitly discussed in class. Here λ is the wavelength of electron and d is distance between the planes. All lecture notes with drawings. 611 pages of flp lecture notes. Potential energy:- It is the energypossessed by the electronby virtue of its position near the nucleus. Lectures. , School Tie-up | (b) Photoelectric current is directly proportional to the intensity of incident light and is independent of its frequency. 0000006454 00000 n Here, r is the radius of curvature, B is the strength of magnetic field, v is the velocity, e is the charge on cathode ray particle and m is  the mass. 8 8 2 8 2 2 − − − == − = − ∆′ ∆ =x x x c v t t. The lifetime of a fast-moving particle is measured by noting how far it travels before decaying. subject, Here, r is the radius of curvature, B is the strength of magnetic field, v is the velocity, e is the charge on cathode ray particle and m is  the mass. Modern Physics (PHYS 323) Academic year. The lecture notes constitute the main reference for the Modern Physics part of the course. Isotopes:- Nuclei having same atomic number Z but different mass number A are called isotopes. Radioisotope:- An isotope, obtained in process of artificial transmutation, which exhibits radioactivity is called a radio-isotope. (e) Stopping potential is independent of the intensity of light. Material from chapter 0, however, is implicitly used in several other places in the notes. Twin paradox … (b) Saturation current is independent of frequency. ncy of light. 8.33 10 sec 0.312 2.6 10 sec 1 0.95 2.6 10 sec 1. Electric field: - E = V/d (e) All the laws of mechanics can be applied to electron revolving in a stable orbit while they are not applicable to an electron in  transition. name, Please Enter the valid Nuclear reaction:- Fission reaction of  U92235can be made to proceed in a controlled manner by slowing down the three emitted neutrons. Gama decay:- Sometimes the daughter nucleus is left in the excited state. Work function:- It is defined as the minimum energy required to pull an electron out from the surface of metal. This note covers the following topics: Quantum Revolution, The Photoelectric Effect, Energy Conservation, Atomic Energy Levels From Spectra, Hydrogen Energy Level Spectrum, Investigating Electrons, Two Slits With Waves, The Planetary Model Of The Atom, The Quantum Picture Of The Atom, Nuclear Physics, The Strong Nuclear Force, Nuclear Decay, Beta … It can be put to following uses: Signing up with Facebook allows you to connect with friends and classmates already It is a highly exothermic reaction and produces energy, on a scale, much higher than that produced in fission. I taught the Phys.323 (Modern Physics) in Fall 2011. news feed!”. 35 15.2. 0000005037 00000 n Isotones:- Nuclei having the same number of neutrons (N) but different atomic number (Z) are called isotones. Einstein’s equation of photoelectric effect:-, (b) ½ mvmax2 = hf – hf0 = h(f- f0) = h [c/λ – c/λ0], Threshold frequency (f0):- f0 = work function/h = W/h, Maximum kinetic energy of emitted photo electrons:-, Threshold wavelength:- λ0 = c/f0 = hc/hf0 = hc/W, Momentum of photon:- p = E/c = h/λ = hf/c, For particle at temperature T, λ = h/√3mKT   (E = 3/2 KT), The wavelength of electron accelerated by potential difference of V volts is:-, (a) Number of photons per sec per m2, np = Intensity/hf, (b) Number of photons incident per second, np = Power/hf, (c) Number of electrons emitted per second = (efficiency per surface)× (number of photons incident per second). Relativity of simultaneity. (a) Nuclear forces are attractive in nature. (d) Nuclear forces decrease very quickly with distance between two nucleons.