What is the Planck-Einstein equation?

Answer 1

The relation between the energy (E) of a photon and the frequency (v) of its associated electromagnetic wave is called the Planck relation or the Planck--Einstein equation:

E = hv

h is the Planck constant which as a value of about 6.626 * 10-34 J*s (a very very small number)

Answer 2

The Planck-Einstein equation describes the energy of a photon, which is a quantum of light. It states that the energy of a photon is directly proportional to its frequency, with the constant of proportionality being Planck's constant. This equation helps to quantify the energy carried by individual photons in electromagnetic radiation.