2006-10-18 03:32:04 · 6 answers · asked by Christa 2 in Science & Mathematics ➔ Physics
The speed of light is less (less than in vacuum) within any transparent material (air, water, glass, etc.), because of the refractive index of the material itself. However, this change in the speed is not the same for any energy of the incoming photon, basically, more the energy of the photon, the more it is slowed.
Since wavelength varies inverse proportinally with the energy, lower wavelengths get slowed more, resulting in the change in refractive index we observe.
The actual reason for this difference in the slow down effect for different wavelengths (or energies) is not known, as far as I could find out, however there are several empirical equations that were theorized to calculate the amount of the effect. The simplest being Cauch's Equation:
n=a+b/(m^2)+c/(m^4)+...
where n is the refractive index and m is the wavelength. a,b,c,... are coefficients specific to a certain material, much like the conventional n (refractive index) we use for different materials.
There are more empirical equations, but the fact that they are only "empirical" shows that while the reason is unknown, the results can be predicted.
Check the links:
2006-10-18 07:30:06 · answer #1 · answered by Grelann 2 · 1⤊ 0⤋
Steve is completely wrong. It is the variance of the refractive index with wavelength (dispersion) in the glass that makes a prism work. The dispersion depends upon the actual material used to make the prism (plastic, fused silica glass, BK7, etc). The different colors are bent to a different degree as they enter the prism and again when they leave, separating the colors into the nice rainbow that we see.
2006-10-18 04:05:20 · answer #2 · answered by AskBrian 4 · 1⤊ 1⤋
Here's the answer I think you're looking for: The refractive index increases as the wavelength decreases (for most normal prism substances). (That's why blue light with shorter wavelength is refracted more).
2006-10-18 04:14:55 · answer #3 · answered by af490 3 · 1⤊ 0⤋
If I could %. a variety of three, then identity choose for dispersion... in spite of the undeniable fact that, technically that's refraction, because of the differing refractive indices of the two supplies (air and glass)
2016-12-26 22:22:14 · answer #4 · answered by mccrow 3 · 0⤊ 0⤋
I doesn't vary with wavelength, the width of the prism itself changes and that is what separates the various wavelengths into different colors of light.
2006-10-18 03:36:00 · answer #5 · answered by SteveA8 6 · 0⤊ 3⤋
Refer 10th std. Science-1 Text Book u'll get it .
2006-10-18 03:54:42 · answer #6 · answered by Anonymous · 0⤊ 1⤋