Planck's Constant (Cynthia)

Planck's constant was discovered and named after Max Planck in 1900. For our purposes, it is used to measure energy emitted as photons. He first proposed this theory as a part of his study of the way in which heated solids emit radiation. He discovered that greater intensity of light means that more photons hit per second and more electrons are ejected. The energy of the outgoing electrons depend on the frequency of light used. Before it was believed that the strength of light was determined by the strength of the protons, rather that the amount of protons.

Max Planck discovered that the energy of the incoming photons is directly proportional to the light frequency This theory can be demonstrated in the equation: E=hf in which h is Planck's constant

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