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Atoms — Physics STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 SciencePhysicsAtoms1 Mark
Question
For question two statements are given-one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer to these questions from the codes (a), (b), (c) and (d) as given below.
  1. Both A and R are true, and R is the correct explanation of A.
  2. Both A and R are true, but R is NOT the correct explanation of A.
  3. A is true, but R is false.
  4. A is false and R is also false.
Assertion (A): According to classical theory, the proposed path of an electron in Rutherford atom model will be circular.
Reason (R): According to electromagnetic theory an accelerated particle continuously emits radiation
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Answer

  1. Both A and R are true, but R is NOT the correct explanation of A.

Explanation:

According to classical electromagnetic theory, an accelerated charge continuously emits radiation. As electrons revolving in circular paths are constantly experiencing centripetal acceleration, hence they will be losing their energy continuously and the orbital radius will go on decreasing and form spiral and finally the electron will fall into the nucleus.

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