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In electrodynamics, the Larmor formula is used to calculate the total power radiated by a nonrelativistic point charge as it accelerates. It was first derived by J. J. Larmor in 1897, in the context of the wave theory of light. When any charged particle accelerates, energy is radiated in the form of electromagnetic waves. For a particle whose velocity is small relative to the speed of light, the total power that the particle radiates can be calculated by the Larmor formula: P = 2 3 q 2 4 π ε 0 c 2 = 2 3 q 2 a 2 4 π ε 0 c 3 = q 2 a 2 6 π ε 0 c 3 = μ 0 q 2 a 2 6 π c  (SI units) P = 2 3 q 2 a 2 c 3  (cgs units) where v ˙ or a is the proper acceleration, q is the charge, and c is the speed of light. A relativistic generalization is given by the Liénard–Wiechert potentials. In either unit system, the power radiated by a single electron can be expressed in terms of the classical electron radius and electron mass as: P = 2 3 m e r e a 2 c One implication is that an electron orbiting around a nucleus, as in the Bohr model, should lose energy, fall to the nucleus and the atom should collapse. This puzzle was not solved until quantum theory was introduced.