Aki Posted December 28, 2003 Report Posted December 28, 2003 Light is a form of energy as we all know. It is massless too, and this is what I don't understand.If we substitute all the numbers into the equation, then: E = mc^2Energy of light = 0 X ( 3x10^8 m/s) So therefore, the energy of light equals to ZERO?????????
Roberto Posted December 29, 2003 Report Posted December 29, 2003 This formula only works for particles at rest. Ligh is never at rest. The correct formula in the general case is E2=m2c4+p2c2, so light has energy E=pc, where p is its momentum. The energy of a photon is also given by the famous formula E=hv, where h is Planck's constant and v is the frequency of the light.
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