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Name: Susan
Status: student
Age: 9
Location: N/A
Country: N/A
Date: 2000-2001


Question:
When the light bends through the prism can we say that the red goes the fastest?


Replies:
Yes, in most cases. In one particular kind of glass, fopr example, the index of refraction (c/v, where c is the speed of light in vacuum and v is the speed of a particular frequency of light in glass) is 1.514 for red light and 1.54 for blue light, so in this case the red light travels at c/1.51, and the blue light travels at c/1.54, so the red light travels 2% faster than the blue light.

Tim Mooney


Yes, indeed, red light is traveling faster through glass than blue light. Red has a smaller index of refraction than blue. Since the index of refraction is the speed of light in a vacuum divided by the speed of light in the material (in this case glass), and red refracts rotten (RRR; blue bends best -- BBB), red light must be going through the glass at a higher speed.

---Nathan A. Unterman


since red light has the largest wavelength, it will have the largest speed when passing through a prism.

Katie Page


Yes, blue light bends the most and red the least through a glass prism. The greater bending of the blue light is a consequence of its slower speed through the glass; conversely, the lesser bending of the red light results from its greater speed.

Richard E. Barrans Jr., Ph.D.
Assistant Director
PG Research Foundation, Darien, Illinois



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