Class name Subject Book title Chapter number Content Created at
Class XII Physics Physics Part-II 4 its electron is revolving in an orbit closest to the nucleus i.e., the one for which n = 1. For n = 2, 3, ... the absolute value of the energyE is ...
Class XII Physics Physics Part-II 4 a photon in the process. ground state, 13.6 eV of energy Thus, as the excitation of hydrogen atom increases (that is must be supplied. (The horizon...
Class XII Physics Physics Part-II 4 energy state and photons are emitted. These spectral lines are called emission lines. But when an atom absorbs a photon that has precisely the same...
Class XII Physics Physics Part-II 4 to standing waves under resonant conditions. From FIGURE 12.8 A standing wave Chapter 14 of Class XI Physics textbook, we know that when is shown o...
Class XII Physics Physics Part-II 4 quantisation of angular momentum of the orbiting electron. The quantised electron orbits and energy states are due to the wave nature of the electr...
Class XII Physics Physics Part-II 4 these atoms more complex electron-electron interactions are nonexistent. Reprint 2026-27 Atoms SUMMARY 1. Atom, as a whole, is electrically neutral...
Class XII Physics Physics Part-II 4 having energy equal to the energy difference between the initial and final states. The frequency (n ) of the emitted photon is then given by hn = E...
Class XII Physics Physics Part-II 4 of electromagnetic radiation of orbiting electrons. 2. What made Bohr quantise angular momentum (second postulate) and not some other quantity? Not...
Class XII Physics Physics Part-II 4 For transitions between large quantum numbers (n to n – 1, n very large), however, the two coincide as expected. 7. Bohr’s semiclassical model base...
Class XII Physics Physics Part-II 4 possesses most of the mass in .......... (Rutherford’s model/both the models.) 12.2 Suppose you are given a chance to repeat the alpha-particle sca...
Class XII Physics Physics Part-II 5 Physics Chapter Thirteen NUCLEI 13.1 I NTRODUCTION In the previous chapter, we have learnt that in every atom, the positive charge and mass are den...
Class XII Physics Physics Part-II 5 unit (u) are close to being integral multiples of the mass of a hydrogen atom. There are, however, many striking exceptions to this rule. For examp...
Class XII Physics Physics Part-II 5 The positive charge in the nucleus is that of the protons. A proton carriesoneunitoffundamentalchargeandisstable.Itwasearlierthought that the nucle...
Class XII Physics Physics Part-II 5 would have to be much higher than is available from the bombardment of beryllium nuclei with a-particles. The clue to this puzzle, which Chadwick s...
Class XII Physics Physics Part-II 5 their number of neutrons. Deuterium, 1H , which is an isotope of hydrogen, contains one proton and one neutron. Its other isotope tritium, 3 , cont...
Class XII Physics Physics Part-II 5 based on pure coulomb repulsion between the positive charges of the aparticle and the gold nucleus. From the distance at which deviations set in, n...
Class XII Physics Physics Part-II 5 – Energy Einstein showed from his theory of special relativity that it is necessary to treat mass as another form of energy. Before the advent of t...
Class XII Physics Physics Part-II 5 However, Reprint 2026-27 Nuclei the nuclear mass M is found to be always less than this. For example, let us consider 18O ; a nucleus which has 8 n...
Class XII Physics Physics Part-II 5 10 kg 2 To convert it into energy units, we multiply it by c and find that energy equivalent = 1.6605 × 10 –27× (2.9979 × 10 ) kg m /s 2 = 1.4924 ×...
Class XII Physics Physics Part-II 5 of the atomic number for nuclei of middle mass number ( 30 < A < 170). The curve has a maximum of about 8.75 MeV for A = 56 and has a value of 7.6 ...
Class XII Physics Physics Part-II 5 property of the nuclear force. (iii) A very heavy nucleus, say A = 240, has lower binding energy per nucleon compared to that of a nucleus with A =...
Class XII Physics Physics Part-II 5 charges or the gravitational forces between masses. The nuclear binding force has to dominate over the Coulomb repulsive force between protons insi...
Class XII Physics Physics Part-II 5 of exposure, the photographic plate was developed, it showed blackening due to something that must have been emitted by the compound and was able t...
Class XII Physics Physics Part-II 5 Thus for the same quantity of matter, nuclear sources produce a million times more energy than a chemical source. Fission of 1 kg of uranium, for e...
Class XII Physics Physics Part-II 5 events first appears as the kinetic energy of the fragments and neutrons. Eventually it is transferred to the surrounding matter appearing as heat....