Question

How there will be no change in angle of revolution when an electron moves in a circular motion in a atom

Answer 1

The force that acts on a partice revolving in a circle is Centripetal Force, not Centrifugal Force.
A rotating partice is accelerated radially inverd and this acceleration is known as Centripetal Acceleration, the force corresponding to this is thus Centripetal Force.

As stated that the rotating particle, here the electron, it will need a centripetal force to move in a circle around the nucleas. This neccessary Centripetal Force is provided by the electrostatic force between the electron and the nucleas.

As long as the electristatic force is present, elctron moves in circular path.anc do not change the angle of revolution.