-->

Atoms

Question
CBSEENPH12047999

Assertion:  Electrons in the atom are held due to Coulomb forces. 

Reason:  The atom is stable only because the centripetal force due to Coulomb's law is balanced by the centrifugal force.

  • If both assertion and reason are true and reason is the correct explanation of assertion.

  • If both assertion and reason are true but reason is not the correct explanation of assertion.

  • If assertion is true but reason is false.

  • If both assertion and reason are false.

Solution

C.

If assertion is true but reason is false.

Assertion is true but reason is false. 

According to postulates of Bohr's atom model, the electron revolves round the nucleus in fixed orbit of definite radii. As long as the electron is in a certain orbit it does not radiate any energy. Not only the centripetal force has to be the centrifugal force, even the stable orbits are fixed by Bohr's theory.