energyopticsrefractionwavelength
I read about the dispersion of light by a prism and a block (slab), but I don't understand why light bends at all.
I know that red light has the longest wavelength and that energy is inversely proportional to wavelength, hence red light contains the least energy. I also know that it bends the least. But why? Why does red light not bend as much as violet light?
Please don't use Snell's law in your answer.
The problem is probably simpler than you think. The light beam is refracted as it passes through the top of the slab, and you can use Snell's Law to calculate the transmitted angle. You'll find the angle is different for the two wavelengths, and question is asking for this difference.
I know that photons/light bends or bounces when it hits glass so if it was in a glass prism where would it go.
Source: Light entering prism
It goes through the prism and two things happen. The white light gets split into the rainbow of colors and it also gets bent (refracted), because each of the colors is a different wavelength than the others. The colors between red and blue get refracted as well, not as much as red but more refracted than blue.
The light can be reflected or refracted or both, as in the picture below.
I don't really understand Snell's law.
The best way to think of Snell's law is to imagine you have to run from a point A to a point C, but on the way you must touch a pole at point B, which is midway between A and C but 50 metres below the straight line connecting A and C. That's the way light works, it gets from A to B and B to C in the shortest time. You should be able to see that on the picture above.
If it went any other way, it would take more time, so the angle it hits B (coming from A), must equal the angle going to C.
I bet you can't think of a quicker way to go this route than the way light goes.
Best Answer
If you don't want (ray-based) Snell's law, then we can do it using the wave aspect. BTW the analogy totally stands with water waves, with the depth playing the role of refraction index. -> when the light waves enter the glass, or when water waves enter shallower water, they slow down and wavelength get shorter. This has the effect of tilting the wavefront, and this is the true cause of change of direction in refraction. And this tilting effect does not have the same amplitude depending of the wavelength (the distance between wave fronts).