I'm teaching about EM waves in astronomy and atmospheric absorption. I use
a remote control, solar cell, and Radio Shack amp/speaker to show that
remotes give IR pulses. These waves are partially blocked by a black
plastic bag and almost totally blocked by white paper or aluminum foil.
They go right through wax paper, clear plastic, and a metal screen.
Does anyone know the frequency (wavelength) range for typical remote
controls (for radios, TVs, DVD players, etc.)?
On a related note, my car remote pulses go through walls. Are these waves
similar to those for remotes I mentioned earlier, or is it in a different
part of the EM spectrum? I have not tried my shields with my car remote
yet.
Any other demos that can be done with these remotes?