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View Full Version : why do accelerated charges emit e/m radiation?


sor2char
Jul2-04, 10:22 AM
Hi first time post here and the site is awesome.
Question is in the title really. Im a second year physicist at UMIST, manchester, England and worry about why an accelerated charged particle loses energy via e/m radiation. For example Bohr's model of the atom consisting of electrons physically orbitting the nucleus was proved incorrect as the elctrons would spiral towards the centre.

DarkEternal
Jul2-04, 10:58 AM
the purcell text i used this year had a very good explanation based in relativity, somewhat replicated at this site: www.chem.yale.edu/~cas/jenkins.html

basically, electromagnetic disturbances propagate at the speed of light. so the information that the charge (and the field from the charge) has acclerated reaches a certain point away from the charge at a later time, indicated by the picture to the right. this creates a sort of wavefront.