Karnataka Board PUCPUC Science 2nd PUC Class 12

In a Radioactive Decay, Neither the Atomic Number Nor the Mass Number Changes. Which of the Following Particles is Emitted in the Decay? - Physics

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MCQ

In a radioactive decay, neither the atomic number nor the mass number changes. Which of the following particles is emitted in the decay?

Options

  • Proton

  • Neutron

  • Electron

  • Photon

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Solution

Photon 

The atomic number and mass number of a nucleus is defined as the number of protons and the sum of the number of protons and neutrons present in the nucleus, respectively. Since in the decay, neither the atomic number nor the mass number change, it cannot be a beta-decay (release of electron, proton or neutron). Hence, the particle emitted can only be a photon.

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Chapter 24: The Nucleus - MCQ [Page 441]

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HC Verma Class 11, Class 12 Concepts of Physics Vol. 2
Chapter 24 The Nucleus
MCQ | Q 12 | Page 441

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