In the spirit of "If it weren't good, it wouldn't be worth critique" : This is dicey for me. Simplifications are okay in teaching as long as they aren't specifically wrong. I find it great to convey that refraction is really a consequence of the scattering and superposition- the observed phase speed is really an outcome, not a cause. Great. But there is a big leap saying that this "explains." It describes in a very simplified way. I would note that *exactly* the same things happens with sound waves traveling into bubble clouds and for the same reasons--there's no quantum mechanics to worry about at all. This can be explained with albeit complicated, classical scattering. Snell's law bears a similar relationship to the real explanation that Newtonian Gravity does to General Relativity: Gives the right answer almost all the time, and was what we once understood, but, if you imbue meaning like "masses attract each other"--well, that is a sort of reasonable memory aid, but it isn't really true, much like saying the speed in glass changes. Second, the difference in dispersion for different wavelengths isn't "explained" here at all...there's a bunch of circular verbage and plausibility stuff about dollars being given and taken away, none of which actually has to do with what is going on at all. You'd be better off with a more approximate simplification: Blue light is scattered differently (in amplitude and phase) than red light (throw in the sky here, if you like) so the interference sum generated is different, and this is what *really* leads to a different implied effective phase speed. www.math.ucdavis.edu/~saito/data/scattering/foldy-multiple-scattering.pdf
Thanks Robert. You make some good points. Makes me consider editing. You are right. If you simplify too much the risk is getting it incorrect. A challenge for use educators at times
@@PhysicsHigh According to me if light enters from air to glass its group velocity is slowing down wrt the phase velocity. It's a matter of energy because why does light have the same speed again when it passes from glass to air?
Thanks a lot sir.I am from India🇮🇳 and i am really grateful that you explained this concept so deeply and nicely. I am in 11 standard and this doubt of mine that you cleared really gave me some foundation for structure of atoms.Again thank you sir🙏🏽
Cuplajul densitatii luminii cu densitatea mediului este dovedita de experienta lui Fizeau, care verifica cu precizie formula lui Fresnel de antrenare partiala a eterului. Formula care se deduce usor, pe modelul de motor electric liniar al fotonului, din insumarea densitatii masice a fotonului cu densitatea masica a mediului transparent si in miscare prin care trece lumina, fara nicio metafizica relativista. The coupling of the density of light with the density of the medium is proven by Fizeau's experience, which precisely verifies Fresnel's formula for the partial entrainment of the ether. The formula that is easily deduced, on the model of the linear electric motor of the photon, from the summation of the mass density of the photon with the mass density of the transparent and moving medium through which the light passes, without any relativistic metaphysics.
In the spirit of "If it weren't good, it wouldn't be worth critique" : This is dicey for me. Simplifications are okay in teaching as long as they aren't specifically wrong. I find it great to convey that refraction is really a consequence of the scattering and superposition- the observed phase speed is really an outcome, not a cause. Great. But there is a big leap saying that this "explains." It describes in a very simplified way. I would note that *exactly* the same things happens with sound waves traveling into bubble clouds and for the same reasons--there's no quantum mechanics to worry about at all. This can be explained with albeit complicated, classical scattering. Snell's law bears a similar relationship to the real explanation that Newtonian Gravity does to General Relativity: Gives the right answer almost all the time, and was what we once understood, but, if you imbue meaning like "masses attract each other"--well, that is a sort of reasonable memory aid, but it isn't really true, much like saying the speed in glass changes. Second, the difference in dispersion for different wavelengths isn't "explained" here at all...there's a bunch of circular verbage and plausibility stuff about dollars being given and taken away, none of which actually has to do with what is going on at all. You'd be better off with a more approximate simplification: Blue light is scattered differently (in amplitude and phase) than red light (throw in the sky here, if you like) so the interference sum generated is different, and this is what *really* leads to a different implied effective phase speed. www.math.ucdavis.edu/~saito/data/scattering/foldy-multiple-scattering.pdf
Thanks Robert. You make some good points. Makes me consider editing. You are right. If you simplify too much the risk is getting it incorrect. A challenge for use educators at times
@@PhysicsHigh According to me if light enters from air to glass its group velocity is slowing down wrt the phase velocity. It's a matter of energy because why does light have the same speed again when it passes from glass to air?
Thanks a lot sir.I am from India🇮🇳 and i am really grateful that you explained this concept so deeply and nicely. I am in 11 standard and this doubt of mine that you cleared really gave me some foundation for structure of atoms.Again thank you sir🙏🏽
Thanks for helping me with my project
Why does dispersion not occur in glass slab
It does but if it’s rectangular, it ‘corrected’ at the other side. To see it the two sides cannot be parallel
Cuplajul densitatii luminii cu densitatea mediului este dovedita de experienta lui Fizeau, care verifica cu precizie formula lui Fresnel de antrenare partiala a eterului. Formula care se deduce usor, pe modelul de motor electric liniar al fotonului, din insumarea densitatii masice a fotonului cu densitatea masica a mediului transparent si in miscare prin care trece lumina, fara nicio metafizica relativista.
The coupling of the density of light with the density of the medium is proven by Fizeau's experience, which precisely verifies Fresnel's formula for the partial entrainment of the ether. The formula that is easily deduced, on the model of the linear electric motor of the photon, from the summation of the mass density of the photon with the mass density of the transparent and moving medium through which the light passes, without any relativistic metaphysics.
it has a few mistakes in equations!