This problem deals with interaction of charged particle bounded by Coulomb interaction accoridng to classical radiation theory.

A particle with mass m and electric charge q is bound by the Coulomb interaction to an infinitely massive particle with electric charge -q. At t=0 its orbit is (approximately) a circle of radius R. At what time will it have spiralled into R/2? (Assume that R is large enough so that you can use the classical radiation theory than quantum
mechanics.)