|Within the light spectrum there is a range
visible to us. Electricity in the form of
lightning is visible. Is there a visible form of
|Question Date: 2003-11-24|
The short answer is: no.
To understand why
this is it is helpful to remember two things.
The first is that light is a wave. This wave
is partially electric and partially magnetic, with
each color corresponding to a certain wavelength.
The second is that your eye sees because the
electric fields that make up the light wave cause
the electrons in your eye to vibrate. However,
only some wavelengths of light can make the
electrons in your eye vibrate enough to see.
These wavelengths are the wavelengths in the
visible spectrum (red, green, blue, etc.) Light
with longer wavelengths (radio waves, micro waves,
infrared, etc.) can't make the electrons in your
eye respond, and neither can light with shorter
wavelengths (ultraviolet, x-rays, gamma rays,
etc.), so you don't see them.
So the slightly
longer answer to your question is that your eye is
really only sensitive to electric waves (i.e.,
light), and even then only to electric waves
within a specific range of wavelengths (i.e., the
visible spectrum). Gravity waves aren't electric
waves and so aren't very good at making electrons
vibrate (gravity is very weak in this sense). In
addition, it is very hard to make gravity waves
with the wavelengths that your eye would notice.
However it is true that if you were to make
incredibly strong gravity waves at the right
wavelengths the electrons in your eye would
respond and you would see the gravity waves, just
as you do light waves. But to do this would be
very nearly impossible.
By the way, the reason
that you "see" lightning is because the flow of
electricity through the air (the lightning bolt)
makes the air so hot that it glows - i.e., it
gives off light. So it is not really the
electricity you are seeing, but rather the hot air
created by the flow of electricity.
I'm sure you know from you're basic science
classes that electricity is carried by moving
electrons. In the gases that make up air, these
electrons are normally strongly attached to the
molecules that they form. However, during a
lighting strike, they're ripped away and can move
about, allowing electricity to flow. This leaves
behind positively charged molecules. The mix of
electrons and positive molecules is called a
plasma. When the negative electrons recombine with
the positively charged gas to re-form stable
molecules, visible light is given off.
what you see.
So, the visible light that you
see from a lightning strike is the same as the
visible light that you see all around you each
day. You are not actually "seeing" electricity,
rather you are seeing evidence of electricity.
Likewise, you can't "see" gravity. However, if you
go to the ocean's edge, you can see the tide rise
and fall. This is a result of the moon's gravity
pulling on the earth. So, yes, just like the
visible evidence of electricity you see in a
lightning strike, visible evidence of gravity is
all around you.
Hope this answers your question,
When you see light of any kind, be it from a
fluorescent lamp or from lighting in a
thunderstorm, you are seeing the same thing. We
cannot separate "electricity" from "light",
because light is actually the joint vibration of
an electric and a magnetic field. We call that
vibration an electromagnetic wave. The retina of
our eyes is sensitive to electromagnetic radiation
within certain energy range. The gravitational
interaction, as far as we know today, is not of
electromagnetic nature, therefore there is no
visible form of gravity.
That is actually an extremely complicated question
you ask. But basically the answer is: We are not
really sure. Physicists are constantly doing
research on the subject to try to better
understand gravity. From what we understand now,
the force of gravity is so fundamentally different
from the electromagnetic force (which light is a
very small part of), that there is no way we can
directly "see" gravity itself. We can however, see
the effects of gravity in things like black holes.
A black hole is an object with so much gravity
that nothing can escape from it, not even light.
So in this way we can see the effect of gravity
acting on light. Hope this helps. I would be glad
to clear up anything that may still be confusing.
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