Although we don't tend to think about these things, the fact that garage door openers operate via radio waves is kind of amazing. The idea that the frequency of an undulating waveform through space is enough to transmit information and command a huge garage door to open is really a stroke of genius.
In fact, you can perform a couple of quick little experiments to show just how much science is really going on with your garage door opener every single day.
For example, if you try to block the signal of your garage door opener with your hand, by covering up the remote as you push the button, you'll probably notice that it doesn't make a difference. Why doesn't your hand stop the radio waves?
But then, if you cover your opener with aluminum or tin foil and then try to push the button, you might notice the garage door doing something a little more interesting... that is, not obeying your command! And why is that?
Then try placing the remote underneath a metal colander (yes, the pasta strainer with holes) and observe what happens. (If you can't figure out how to push the button while keeping it under the colander, try a metal skewer!) What happens? Does the door open?
And last but not least, try putting a portable radio next to the opener and tuning it up and down the spectrum, pushing the button, to see if at any point it interferes with the communications.
What causes some things to block radio wave communication and not others? Stay tuned to find out!