Radio waves vs light waves

Particles of light that do not make it through the window and which are not
reflected by the surface are absorbed into the structure. The excess energy
is then radiated away as heat.


Sort of.

They are absorbed, which means the (electromagnetic) energy is converted into
other kinds of energy in the structure, be it raising the orbitals of
electrons, wiggling the atoms around a bit, or accelerating it. The excess
energy is not really "excess" as there is no amount of energy a structure is
"permitted" to have. (not counting enough energy to blow it up. Molecular
motion IS heat. One of the ways energy is dissipated is the ratdiation of
photons (light, be it infra-red or otherwise), another is physical transfer of
momentum (the structure's atoms bounce against air molecules and make the air
molecules go faster). There are more.


The difference between a particle and a wave is the difference between
ripples on the water and the stone you threw in there.


No, the stone and the water are different things. But light, whether thought
of as waves or as particles, is the same thing. And if you think of light as a
particle, you are wrong. If you think of it as a wave, you are also wrong.
That's just the way the universe was put together - it's not my fault. g.


It is a fundamental axiom of physics that for very small particles
you can measure either the wave or the particle, but not both
simultaneously.


True enough.


The reason is there is nothing small enough to see both.


Never thought of it that way, but I don't think it's quite right. I thnk the
reason is more fundamental. "Stuff" is just made of something we don't
understand, and the ways we have though of so far are inadequate when put to
the test, though they make perfect sense in the macroscopic sense.


The light bulb does not create photons. It emits photons that are already
stored in the bulb.


The bulb too does create photons... photons that didn't exist before. It does
so by resisting the motion of electons, and therefore sucking some of their
energy into making the bulb hot, and this releases energy in the form of
photons.

Ok, so just what IS a photon?

Think of an electric field that points up and down, and keeps on switching
directions at some rate. Now think of a magnetic field that points left and
right, but switches directions at the same rate, just a bit out of phase. As
the electric field collapses it generates a magnetic field, and as the magnetic
field collapses it generates an electric field, and the two chase each other at
the speed of light. It's not a perfect description, but it's pretty close to
what a photon is.

It takes energy to make these fields wiggle like that, the energy comes from
the motion of electons in their orbitals. When things happen just right, the
electron collapses, exhausted, back into a lower orbital, and a spurt of energy
in the form of the wiggling Electric and Magnetic fields shoots out. A photon
has been emitted. That's where they come from.

Jose


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