atoms and nuclei

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Introduction - In the nineteenth century scientists saw enough evidence to prove that each element has its distinctive atom. But all tem atoms contain identical electrons. In spite of the fact that electrons carry negative charge, atoms as whole were found to be neutra..

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. Further, as electron would lose energy continuously, the atoms should emit electro-magnetic waves over a continuous range. But atoms emit only discrete frequency wavelengths only. From alpha ray scattering experiment, Rutherford calculated distance (r o ) of closest approach o..

Introduction - In the nineteenth century scientists saw enough evidence to prove that each element has its distinctive atom. But all tem atoms contain identical electrons. In spite of the fact that electrons carry negative charge, atoms as whole were found to be neutra..

12. - The half-life of 92 U 238 against alpha decay is 4.5 x 109 years. How many disintegrations per second occur in 1 g of 92 U 238 ? Suggested solution: Again, since one k mole of any isotope contains Avogadro's number of atoms, there fore 1 g of 92 U 238 contains Half life T = 4.5 10 9..

01. - What is the distance of closest approach to the nucleus of an alpha particle which undergoes scattering by 180 o in the Gelger- Marsden experimen..

11. - If 200 MeV energy is released in the fission of a sample nucleus of 9 2 U 2 3 5 , how many fissions must occur per second to produce a power of 1 k..