Which travels more slowly in glass, red light or violet light?
Why? What is your argument?
You need to know how the index of refraction depends on the wavelength, a dispersive effect.
what? all the question asks for is a color...
they both travel at the speed of light, it's the same
The speed of light in the glass is not the same for all wavelengths. The index of refraction is frequency - wavelength dependent, otherwise there would br no spectrum from a prism.
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