German physicist Max Plank stated that energy is emitted in discrete units called quantum. Using Plank’s constant, h, he was able to relate the amount of energy of wave or particle to its frequency using the following equation:
E=h υ
- E= energy
- h= Plank’s constant (h= 6.63 x 10 -34 J s)
- υ = frequency
Example: When copper is bombarded with high-energy electrons, X rays are emitted. Calculate the energy (in joules) associated with the photons if the wavelength of the X rays is 0.122 nm.
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