Figure 3.4 A simple model of the helium atom and the electrostatic forces involved
Solution: First, the repulsion forces between the electrons and attraction forces between electrons and protons are calculated. The net force is balanced by the centrifugal force due to orbiting of the electron. This gives the angular velocity required:
(a) The direction of the electrostatic force is radial. The two electrons repel each other, whereas the electrons are attracted to the protons. The repulsion forces between electrons are