: As we all know, an atom is consisted out of a positively charged part-nucleus arond which orbit the particles called electrons. since we know that the nucleus is positively charged and electrons negatively, what stops the electron from falling on the nucleus of the atom????

Nobody knows. But it's described by saying that the atom (i.e. electron/nucleus system) can only be in a certain states. The falure to describe the stability of the atom was what led physicists to create quantum physics.

Consider the fact that the Earth is being attracted to the Sun in a similar way. The Earth doesn't fall into the Sun because it's in orbit around the Sun. The physics of orbits can be explained with Newtonian mechanics. The same cannot hold for the atom. When an electron moves in a circle its accelerating. An accelerating charge radiates energy continuously. Classicaly the result should be the elctron falling into the nucleus. However we now know that Newtonian mechanics does not hold at the atomic level. The atom can only radiate in discrete amounts.

• Re: Electrons - Zephram_Cochrane/">Zephram Cochrane - February 25, 2000 - 21:59 UTC