The Positive charged nucleus of an atom attracts the electron in the orbits. Why do the electrons not collapse into the nucleus?

Ans: For an electron revolving around the positively charged nucleus, the required centripetal force is provided by the force of attraction which is along the tangent at any point of the circular path. The centripetal force, which is directed radially towards the centre of the circular path, has no effect on the tangential velocity. That's why, the electron continues to move around the circular path and it doesn't collapse into the nucleus.

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