Are the electrons spinning around the nucleus of an atom travelling faster than the speed of sound?

Asked by: Madhur Upman

Answer

The electrons do not really 'spin' around the nucleus in atoms. They are found in what is called 'orbitals', which are three-dimensional probability distributions, which correspond to the quantum mechanical state they are in. The way things work in such microscopic scales is very much different from our everyday experience, and has a 'logic' of its own, and is (in my opinion) very fascinating.

However, not to give the feeling the question is being fended off without an answer, let me mention this: In the Bohr model of the Hydrogen atom (which gives some right answers, but is known to be essentially incorrect) electrons _do_ spin around the nucleus. In the simplest case of a hydrogen atom with a single electron spinning around a single proton, the electron moves at about 1/137 of the speed of light, which is MUCH faster than sound. Sound travels at about 1100 feet per second, while light travels at 186,000 miles per second.. You do the math.

As a side note, with the Bohr model, the 'inner' electrons in atoms with greater atomic numbers would be moving faster...
Answered by: Yasar Safkan, Ph.D. M.I.T., Software Engineer, Istanbul, Turkey