Atoms
In 1913 Neils Bohr proposed a model of hydrogen based on a particle in an orbit
electron with charge -e in a circular orbit about a nucleus of charge +Ze
Coulomb attraction provides centripetal force mv2/r= kZe2/r2
potential energy is U= kq1q2/r = -kZe2/r
kinetic energy K=(1/2)mv2=(1/2)kZe2/r
hence U= -2K (same for gravity!)
total E= K +U = -K = -(1/2)kZe2/r
e/m theory states that an accelerating charge radiates energy!
Should spiral into the nucleus!