Ncert 12th Physics Chapter-12

Bohr’s Model of Hydrogen Atom

Bohr combined classical and early quantum concepts and give his theory in the form of three postulates. (I) Bohr’s first postulate was that an electron in an atom could revolve in certain stable orbits without the emission of Radiant energy. According to this postulate, each atom has certain definite stable state in which it can exist …

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Drawbacks of Rutherford’s Model

Rutherford’s model suffers to major drawbacks. 1. Stability of Atom: According to Maxwell, an accelerated charged particles emits radiation(energy). In Rutherford Model of atom, electrons are moving in circular orbits, Thus having centripetal acceleration. So electrons should emits radiation and ultimate lose energy and pulled into nucleus and atom would not be stable. So Rutherford …

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Distance of Closest Approach, Impact Parameter and Electron Orbits

Distance of Closest Approach: As the Distance particle approaches the nucleus, the electrostatic force of repulsion due to nucleus increases and the kinetic energy of α particle goes on converting into the electrostatic potential energy. At a certain distance r₀ from the nucleus, whole of the kinetic energy of α particle convert into electrostatic potential energy …

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All elements consists of a very small invisible particles are called atoms. Atoms of some elements are same and atoms of different elements are different. #The first model of atom was proposed by JJ Thomson in 1898 called plum pudding model. According to this model, the positive charge of the atom is uniformly distributed throughout …

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