Welcome back guys.
In this new video, we're going to take a look
at the nature of light.
Now, what we should realize is the visible
light that we see with our eyes, it only represents
a small section of all the possible lights
that exists.
The visible light that we see has a certain
energy tied with it.
Now, there are light sources that are above
that energy and below that energy.
Taking into account all of these different
types of energies, we have this image right
here.
This is known as our electromagnetic spectrum.
You should see that we have here, these are
gamma rays, we have X-rays, UV, here this
is infrared, IR.
Now, between UV which is ultraviolet light
and IR, which is infrared light, that's what
we find our visible light spectrum.
We're going to say our visible light spectrum—the
range is really 390 nm to about 780 nm.
We learned this in the school, roygbiv, so
roygbiv.
Remember, what is that stand for?
We're going to say red, orange, yellow, green,
blue, indigo and violet.
We're going to say here, it looks like violet,
violet is around 400 nm, whereas red is around
780 nm.
Remember, the visible light spectrum only
represent a small section of the entire spectrum
of colors.
Now, after IR, there are these microwave,
then we have radio waves, which we get in
our car radios or at home, on our stereos.
We have FM and then we have radio in between
AM and then we have long radio waves.
These represent basically all the different
types of light sources or light energies that
exist.
There is also a cosmic rays which are usually
above gamma, the professors usually ignore
those.
