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Model Paper 8 — Science STD 9 — Question

Gujarat BoardEnglish MediumSTD 9ScienceModel Paper 81 Mark
MCQ
Assertion (A): Rutherford's atomic model was that it could not explain the stability of atoms.
Reason (R): Any charged particle during acceleration would radiate energy, and while revolving, it would lose its energy and eventually fall into the nucleus.
  • ✓
    Both A and R are true and R is the correct explanation of A
  • B
    Both A and R are true but R is not the correct explanation of A
  • C
    A is true but R is false.
  • D
    A is false but R is true.
✓

Answer

Correct option: A.
Both A and R are true and R is the correct explanation of A
(a) Both A and R are true and R is the correct explanation of A.
Explanation: Rutherford’s atomic model could not explain how moving electrons could remain in their orbits. Any charged
particle during acceleration would radiate energy, and while revolving, it would lose its energy and eventually fall into the
nucleus. This means that the atom would be highly unstable. But, the matter is composed of stable atoms. Thus, the major
drawback of Rutherford’s atomic model was that it could not explain the stability of atoms.

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