why does a prism creates differnt color when light passes through it?

Answer 1

Light changes speed as it moves from one medium to another (for example, from air into the glass of the prism). This speed-change causes light striking the boundary between two media at an angle to be refracted and enter the new medium at a different angle (Huyghens principle), or to be reflected away from it. The amount of reflected light and the degree of bending of the light's path will depend on the angle that the incident beam of light makes with the surface, and on the ratio between the refractive indices of the two media (Snell's law). The refractive index of a medium varies with the wavelength or color of the light used, a phenomenon known as dispersion, and this causes light of different colors to be refracted differently and to leave the prism at different angles, creating an effect similar to a rainbow. This effect can be used to separate a beam of white light into its constituent spectrum of colors.

In Isaac Newton's time, some believed that prisms created new colors. Newton passed individual colors from one prism's spectrum through a second prism and found the color unchanged, and concluded from this that that these different colors must have already been present in the original light — the prism did not create new colors, but merely separated the colors that were already there. He also used a lens and a second prism to recompose the rainbow back into white light. This experiment has become a classic example of the methodology introduced during the scientific revolution. The results of this experiment dramatically transformed the field of metaphysics, leading to John Locke's primary vs secondary quality distinction.

Prisms are sometimes used for the internal reflection at the surfaces rather than for dispersion. If light inside the prism hits one of the surfaces at a sufficiently steep angle, total internal reflection occurs and all of the light is reflected. This makes a prism a useful substitute for a mirror in some situations.

Answer 2

White light consists of a range of colors. For every wavelength, there is a different angle of refraction when it enters the prism. While passing through the prism, the colors will follow unparallel paths. But when they reach the surface going back to the original medium (probably the air) each color refracts again. The angle is the same angle, but with a minus sign. In a prism the 2 surfaces are not parallel, so the colors head off at an angle to the original path but the colors are again parallel. If instead of a prism, they went through a thick piece of glass, then they each return to the original compass heading - just offset to the side a bit.

Answer 3

White light consists of many wavelengths and they get split up in the prism.

Answer 4

Light is actually an electromagnetic wave of different frequencies, which is not visible to naked eye without the aid of refracting prism.

Even the horizon and sky are of different colors is due to refractions, dispersions that takes place above us.

Answer 5

Because white light is actually made up of all the colors of the rainbow.