Einstein-Planck law

Einstein-Planck law

[¦īn‚stīn ¦pläŋk ‚lȯ]
(quantum mechanics)
The law that the energy of a photon is given by Planck's constant times the frequency.
(relativity)
The equation of motion of a charged particle in an electromagnetic field, according to which its rate of change of momentum is equal to the Lorentz force, where the magnitude of the momentum is mv /(1 - v 2/ c 2)1/2, where m and v are the particle's mass and velocity, and c is the speed of light.