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PHYSICS PRINCIPLE TO CONSIDER: The second law of thermodynamics states that the closer a system gets to equilibrium the more disordered it becomes.  It is a basic principle of physics that we must spend energy to impose higher order.  The amount of disorder in a system is called entropy. **QUESTION TO PONDER: Why don't we have to add some form of energy to a glass prism to separate the entering white light into the color bands we see when the same light exits the prism?    Clearly, the light is more organized (possessing higher order) when it exits the prism than when it entered.   The color bands, or "rainbow" we see represents an organization of the photons by energy level (wavelength/ frequency), yet the prism spent no energy doing this task.   How does this make sense from the perspective of entropy? PLEASE RESPOND TO: mantissa3@oocities.com

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* Some of the energy in the white light is absorbed in the process of refraction, if you were to take the wattage of the white light and compare it to the sum wattage of the spectrum refracted through the prism, the White light will have greater wattage.  Some of the white light is reflected, but the comparison still holds true.  The energy absorbed is that energy required for the ordering of the spectra.  Maxwell's equations apply here. * I thought that a prism did use energy.  It is powered by light, right?  Does it emit the same quantity that it absorbs? * I believe that is the key question in this puzzling discussion! * Well, there are exceptions to every rule, and I think we have found one here. * I have been pondering your prism prediciment.  If the light being emitted is measured down to the smallest degree that can be measured, and perhaps even to a degree that can not be measured, I'll bet that the light going in is more than the light going out.  I'll also bet that if you measure the temperature of the prism before and after exposure to light, that it will be warmer after.  Some of the energy going in is lost to warming the prism, and the rest is emitted as diffused light. * Maybe the prism actually absorbs some of the energy of the incoming light so that the light coming out is organized, but there are fewer total photons. * The photons slow down inside of the prism according to their frequencies, and the sum of all energies coming out of the prism will not be the same as the sum of all energies coming into the prism. The prism itself doesn't dissipate energy, it just causes the photons to lose some energy. Plus, some of the energy (and entropy) comes out as heat. --this response submitted by:  Andrew Mihal--