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प्रश्न
A certain nucleus has a mass number 20 and atomic number 9. Find the number of neutrons and protons present in it.
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उत्तर
(i) Number of neutrons = Mass number – Atomic number
= 20 – 9 = 11
(ii) Number of protons = Atomic number = 9.
संबंधित प्रश्न
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(i) the purpose of covering cathode by thorium and carbon.
(ii) the purpose of the fluorescent screen.
(iii) how is it possible to increase the rate of emission of electrons.
Give a scientific explanation.
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Reason (R): Rutherford did α-particles scattering experiment.
