I remember that we found that entirely obvious (well, most of us) in my high-school physics class.
What I still don't understand, though, is how photons can "wave" or how "long" a photon is (or how they can have any "length" at all).
What I also didn't understand back then was how light can be slower when there is matter present -- or how a photon could somehow know that it was supposed to cause another, very similar, photon to be released in just the right angle when it hit something that, if zoomed out enough, looked like a mirror. How on Earth could the photon know that the photon it was hitting was part of a flat surface and what its orientation was? I even started using that mirror question as a litmus test of physics students once I started at uni (comp.sci.) -- pretty much all of them failed, not by not knowing the answer but by not understanding that this was even a question that required an answer.
I now know that the photon -- the wave(s) in the electromagnetic field -- cause atoms (and in particular their electrons) to move about a bit, which in turn cause waves in the electromagnetic field. And by adding up all these waves, we get the resulting wave which moves slower than c and which might seem to have been reflected at an angle. Why my physics teacher in high-school didn't tell us that, I don't know.
What I still don't understand, though, is how photons can "wave" or how "long" a photon is (or how they can have any "length" at all).
What I also didn't understand back then was how light can be slower when there is matter present -- or how a photon could somehow know that it was supposed to cause another, very similar, photon to be released in just the right angle when it hit something that, if zoomed out enough, looked like a mirror. How on Earth could the photon know that the photon it was hitting was part of a flat surface and what its orientation was? I even started using that mirror question as a litmus test of physics students once I started at uni (comp.sci.) -- pretty much all of them failed, not by not knowing the answer but by not understanding that this was even a question that required an answer.
I now know that the photon -- the wave(s) in the electromagnetic field -- cause atoms (and in particular their electrons) to move about a bit, which in turn cause waves in the electromagnetic field. And by adding up all these waves, we get the resulting wave which moves slower than c and which might seem to have been reflected at an angle. Why my physics teacher in high-school didn't tell us that, I don't know.