Why does a Microwave Oven have Hot Spots?
Oh, and now we have to combine the two waves, like we had to in the
Two Slit Experiment, except here we have to
add two whole surfaces, not just two lines...
Exactly. It's a little harder to visualize, but its the same kind of thing. The result looks like this:
Cool! The high and low areas in that picture match the pattern we saw in the marshmallow
experiment. But wait a second, I have two problems with this. First, if the waves are moving
at the speed of light, shouldn't the hot spots be moving, too? Also, does this mean that all
microwave ovens have TWO "microwave guns"? I mean, one for the back and forth waves and one
for the front to back waves?
Not only are those both good questions, but they have the same answer. The "microwave guns"
are called "magnetrons" and a microwave oven only has one of them. We get two different wave
patterns because the physics of a microwave oven leads to something called Standing Waves...