| Class XII |
Physics |
Physics Part-II |
4 |
R He gave a theory of nuclear frequency of the electromagnetic waves emitted by the fission based on the liquidrevolving electrons is equal to the ... |
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| Class XII |
Physics |
Physics Part-II |
4 |
Bohr studied in Rutherford’s laboratory for several months in 1912 and he was convinced about the validity of Rutherford nuclear model. Faced with ... |
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| Class XII |
Physics |
Physics Part-II |
4 |
and final states. The frequency of the emitted photon is then given by hν = E –iE f (12.6) where E aid E arf the energies of the initial and final ... |
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| Class XII |
Physics |
Physics Part-II |
4 |
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 smal... |
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| Class XII |
Physics |
Physics Part-II |
4 |
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 horizonta... |
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| Class XII |
Physics |
Physics Part-II |
4 |
state and photons are emitted. These spectral lines are called emission lines. But when an atom absorbs a photon that has precisely the same energy... |
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| Class XII |
Physics |
Physics Part-II |
4 |
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 on a... |
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| Class XII |
Physics |
Physics Part-II |
4 |
of angular momentum of the orbiting electron. The quantised electron orbits and energy states are due to the wave nature of the electron and only r... |
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| Class XII |
Physics |
Physics Part-II |
4 |
atoms more complex electron-electron interactions are nonexistent. Reprint 2026-27 Atoms SUMMARY 1. Atom, as a whole, is electrically neutral and t... |
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| Class XII |
Physics |
Physics Part-II |
4 |
energy equal to the energy difference between the initial and final states. The frequency (n ) of the emitted photon is then given by hn = Ei– E f ... |
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| Class XII |
Physics |
Physics Part-II |
4 |
electromagnetic radiation of orbiting electrons. 2. What made Bohr quantise angular momentum (second postulate) and not some other quantity? Note, ... |
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| Class XII |
Physics |
Physics Part-II |
4 |
transitions between large quantum numbers (n to n – 1, n very large), however, the two coincide as expected. 7. Bohr’s semiclassical model based on... |
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| Class XII |
Physics |
Physics Part-II |
4 |
most of the mass in .......... (Rutherford’s model/both the models.) 12.2 Suppose you are given a chance to repeat the alpha-particle scattering ex... |
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| 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... |
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| 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... |
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| 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... |
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| 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... |
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| 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... |
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| 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... |
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| 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... |
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| 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... |
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| Class XII |
Physics |
Physics Part-II |
5 |
of MeV. Thus for the same quantity of matter, nuclear sources produce a million times more energy than a chemical source. Fission of 1 kg of uraniu... |
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| 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 ... |
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| Class XII |
Physics |
Physics Part-II |
5 |
independent 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 v... |
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| Class XII |
Physics |
Physics Part-II |
5 |
saturation property of the nuclear force. (iii) A very heavy nucleus, say A = 240, has lower binding energy per nucleon compared to that of a nucle... |
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