🚀 go-pugleaf

Hi,

I'm a high school physical science teacher struggling to make sense of
light's dual nature, and communicate its interaction with matter in a
clear fashion students. Could someone here help me by answering a few
questions?

1) Violet light is slowed more than red light as it passes through glass
because violet "interacts" more with the electrons therein. As I
understand it, this is because most glass absorbs UV frequencies which are
closer to violet than to red. If I treat electrons as harmonic
oscillators, I can imagine this. But from the quantum mechanical
perspective, why would certain molecules have electrons that absorb UV,
but not IR? I know it has to do with their arrangement (orbitals, and
bonding, and so on), but I'd like to understand this better from a quantum
mechanical perspective. Is it the electron's tendancy to leap from energy
level x - to - energy level y that determines its resonant frequency?

2)  And water absorbs microwave frequencies, so why in the world does it
also slow violet more than red? Shouldn't it be better at slowing the red
because red is closer to the frequencies it absorbs?

3) Then there's scattering. Are the frequencies that get emitted the same
ones that were absorbed? And besides, I thought that if you hit a molecule
with its own resonant frequencies that it would absorb them and heat up,
not re-emit them. So why do microwaves heat up water molecules, and not
get scattered?


Thanks very much,

Kevin Luttrell
Polytechnic High School