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Dec
22
revised Controllable faster-than-light phase velocity
expanded answer
Dec
22
answered Controllable faster-than-light phase velocity
Dec
16
comment Reflected and refracted wave sphased
A phase conjugated mirror's effect is non-linear, but the Goos-Hänchen effect takes place in linear media. It has to do with the penetration depth of the wave into the medium, if I remember correctly.
Dec
16
revised Reflected and refracted wave sphased
edited tags
Dec
16
answered Reflected and refracted wave sphased
Dec
16
awarded  Organizer
Dec
15
awarded  Enlightened
Dec
15
awarded  Nice Answer
Dec
11
awarded  Nice Answer
Dec
11
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Dec
8
comment Is there a travelling speed of for electric field? If yes, what is it?
possible duplicate of Is electricity instantaneous?
Dec
8
comment Is there a travelling speed of for electric field? If yes, what is it?
Are you sure that photons travel through the wire? If the current is DC, then the frequency of these photons is 0, and so according to $E=\hbar\omega$ they have no energy? I always thought that it was just a disturbance in the electric field.
Dec
8
comment Is there a travelling speed of for electric field? If yes, what is it?
Huh? So even the one-meter wire would cause the bulb to light 2 hours and 47 minutes after you flip the switch?
Dec
7
comment Why does dust stick to rotating fan propeller?
Fans can often be found in kitchens, which makes them even more likely to be sticky with oil. Maybe not your fan, but I'm sure this explanation accounts for at least half the dust found on fan blades!
Dec
7
comment Theoretical Physics - How to?
Looking back on my answer, I see you might have interpreted it as saying that a theorist had to be an excellent experimenter too - I've edited it to say what I really meant, which is just that it's important not to ignore experimenting.
Dec
7
revised Theoretical Physics - How to?
edited to clarify intent
Dec
6
answered Theoretical Physics - How to?
Dec
3
comment Deriving the speed of the propagation of a change in the Electromagnetic Field from Maxwell's Equations
If you want to learn more, a good book to read is David J. Griffiths' Introduction to Electrodynamics, chapter 9.
Dec
2
comment Why does my watch act like a mirror under water?
@Frédéric: OK, I'm convinced - as you say, $n\sin\theta$ is the same in each material. What I didn't think of is that if your eye is directly above the watch and the water surface, there is no refraction there, so it's as if you were observing underwater. Also, with more careful observation of my watch, I determined the angle at which it happens was closer to 50 degrees, so this agrees more with the critical angle of 48.7 degrees.
Dec
2
answered An iPhone falling on carpet is fine, is it true?