Assertion : Electron in an atom is held in circular orbits around the nucleus by Coulomb forces.

Reason : The necessary centrifugal force, Fc, to keep the rotating electrons in their orbits is provided by the electrostatic force of attraction, Fe, between the nucleus and the electrons.

A is true but R is false.

It is actually the necessary Centripetal force (Fc) which keeps the electrons rotating in their orbits and this forces is provided by the electrostatic force of attraction, Fe, between the nucleus and the electrons.