Sound vs light

Sound differs from light in several ways: Both are thought of as waves,
but different kinds of waves: Elastic and inelastic.

Sound is considered to consist of elastic compressional waves of the
atomic and molecular particles which - according to the kinetic theory
- comprise various substances and its speed is the mean speed of those
atomic and molecular particles; which vary in various substances;
depending on their density.

Being elastic, explains how sound - radiating from a source - carries
or spreads around corners, and through orifices, where it spreads out
again.

Light is considered to consist of "longitudinal waves", each being an
entity in itself something like this ~~~~~ so that light radiates -
from a source - radially in straight lines; but not being elastic,
these rays of light don't readily spread around corners or after
passing through orifices; except as they may reflect from other
surfaces.

The squiggly nature, wave length or phase pattern of light rays have a
unique attribute in that when passing through certain double slits, and
prisms, the wave length or phase pattern of the emerging rays is
altered so that they may appear as different colors, or even be
cancelled.

Has anyone any other ideas?

Don

Don1 wrote:
Sound differs from light in several ways: Both are thought of as
waves,
but different kinds of waves: Elastic and inelastic.

Wrong. Inelastic waves?


Sound is considered to consist of elastic compressional waves of the
atomic and molecular particles which - according to the kinetic
theory
- comprise various substances and its speed is the mean speed of
those
atomic and molecular particles;

Wrong. If this were true then sound would travel faster in gases then
they do in liquids, which is experimentally not the case.

which vary in various substances;
depending on their density.

Being elastic, explains how sound - radiating from a source - carries
or spreads around corners, and through orifices, where it spreads out
again.

Light is considered to consist of "longitudinal waves",

Wrong. Light is "tranverse waves". Look it up.

each being an
entity in itself something like this ~~~~~ so that light radiates -
from a source - radially in straight lines; but not being elastic,
these rays of light don't readily spread around corners or after
passing through orifices;

Ah but they do. The spreading of the waves has to do with the relative
size of the orifice to the wavelength of the wave. Visible light waves
have a *much* smaller wavelength than audible sound waves. This is the
*only* reason for the difference in the behavior. If you make an
orifice that is comparable in size to the light wave, then the
spreading becomes just as dramatic as sound waves.

except as they may reflect from other
surfaces.

The squiggly nature, wave length or phase pattern of light rays have
a
unique attribute

Wrong. It is not unique. The same phenomenon occurs with sound, which
is why you can get dead spots with a stereo if you have a poorly
designed room for sound.

in that when passing through certain double slits, and
prisms, the wave length or phase pattern of the emerging rays is
altered

Wrong again. The wavelength is not altered by passing through the slits
or even on emerging from a prism. (In the latter case, the wavelength
emerging from the glass is the same as the wavelength entering the
glass.)

so that they may appear as different colors, or even be
cancelled.

Has anyone any other ideas?

Don

Holy smokes, Don, there was so much crapola in that post, so many
blatantly wrong statements, I almost didn't know where to begin.

PD

Dear PD:

"PD" wrote in message
oups.com...

Don1 wrote:
Sound differs from light in several ways: Both are thought of
as
waves,
but different kinds of waves: Elastic and inelastic.

Wrong. Inelastic waves?

The moustraps in the movie Mouse Hunt?

David A. Smith

"Don1" wrote in message
oups.com...
Sound differs from light in several ways: Both are thought of as waves,
but different kinds of waves: Elastic and inelastic.

Sound is considered to consist of elastic compressional waves of the
atomic and molecular particles which - according to the kinetic theory
- comprise various substances and its speed is the mean speed of those
atomic and molecular particles; which vary in various substances;
depending on their density.

Being elastic, explains how sound - radiating from a source - carries
or spreads around corners, and through orifices, where it spreads out
again.

Light is considered to consist of "longitudinal waves", each being an
entity in itself something like this ~~~~~ so that light radiates -
from a source - radially in straight lines; but not being elastic,
these rays of light don't readily spread around corners or after
passing through orifices; except as they may reflect from other
surfaces.

The squiggly nature, wave length or phase pattern of light rays have a
unique attribute in that when passing through certain double slits, and
prisms, the wave length or phase pattern of the emerging rays is
altered so that they may appear as different colors, or even be
cancelled.

Has anyone any other ideas?

Read a physics book

SR

Don

"Don1" wrote in message
oups.com...
Sound differs from light in several ways: Both are thought of as waves,
but different kinds of waves: Elastic and inelastic.

Sound is considered to consist of elastic compressional waves of the
atomic and molecular particles which - according to the kinetic theory
- comprise various substances and its speed is the mean speed of those
atomic and molecular particles; which vary in various substances;
depending on their density.

Being elastic, explains how sound - radiating from a source - carries
or spreads around corners, and through orifices, where it spreads out
again.

Light is considered to consist of "longitudinal waves", each being an
entity in itself something like this ~~~~~ so that light radiates -
from a source - radially in straight lines; but not being elastic,
these rays of light don't readily spread around corners or after
passing through orifices; except as they may reflect from other
surfaces.

The squiggly nature, wave length or phase pattern of light rays have a
unique attribute in that when passing through certain double slits, and
prisms, the wave length or phase pattern of the emerging rays is
altered so that they may appear as different colors, or even be
cancelled.

Has anyone any other ideas?

Don

I know it's not exactly fundamentall physics but your light / sound
differences blah sparked off the weird idea that you could suspend an
enormous sound mirror ball in discoteques (if such things still exist) and
beam different tunes at it so that the go-go crowd would have something
different to dance to as the different sound spots fell on them. What do you
think?

Best of Luck - Mike

Mike Yarwood wrote:
"Don1" wrote in message
oups.com...
Sound differs from light in several ways: Both are thought of as
waves,
but different kinds of waves: Elastic and inelastic.

Sound is considered to consist of elastic compressional waves of
the
atomic and molecular particles which - according to the kinetic
theory
- comprise various substances and its speed is the mean speed of
those
atomic and molecular particles; which vary in various substances;
depending on their density.

Being elastic, explains how sound - radiating from a source -
carries
or spreads around corners, and through orifices, where it spreads
out
again.

Light is considered to consist of "longitudinal waves", each being
an
entity in itself something like this ~~~~~ so that light radiates -
from a source - radially in straight lines; but not being elastic,
these rays of light don't readily spread around corners or after
passing through orifices; except as they may reflect from other
surfaces.

The squiggly nature, wave length or phase pattern of light rays
have a
unique attribute in that when passing through certain double slits,
and
prisms, the wave length or phase pattern of the emerging rays is
altered so that they may appear as different colors, or even be
cancelled.

Has anyone any other ideas?

Don

I know it's not exactly fundamentall physics but your light / sound
differences blah sparked off the weird idea that you could suspend an

enormous sound mirror ball in discoteques (if such things still
exist) and
beam different tunes at it so that the go-go crowd would have
something
different to dance to as the different sound spots fell on them. What
do you
think?

Best of Luck - Mike

Well I hate to put a wet blanket on such a good idea; except that it
wouldn't work! The elastic nature of sound "beams" would create a
cataclysm of sounds indistinguishable from each other: It wouldn't be
pleasant like the inelastic beams of color reflecting off of those many
light mirror facets on a turning central globe; that we used to dance
to before the "dark days" of strob lights.

Don

"Don1" wrote in message
oups.com...

Well I hate to put a wet blanket on such a good idea; except that it
wouldn't work! The elastic nature of sound "beams" would create a
cataclysm of sounds indistinguishable from each other: It wouldn't be
pleasant like the inelastic beams of color reflecting off of those many
light mirror facets on a turning central globe; that we used to dance
to before the "dark days" of strob lights.

Don, don, don.... didn't you see PDs reply to your original post? It is so
full of crap he almost didn't know where to start..

Why don't you learn something simple like f=ma before you start broadcasting
more of your ignorance for all to see.

PD wrote:
Don1 wrote:
Sound differs from light in several ways: Both are thought of as
waves,
but different kinds of waves: Elastic and inelastic.

Wrong. Inelastic waves?


Sound is considered to consist of elastic compressional waves of
the
atomic and molecular particles which - according to the kinetic
theory
- comprise various substances and its speed is the mean speed of
those
atomic and molecular particles;

Wrong. If this were true then sound would travel faster in gases then
they do in liquids, which is experimentally not the case.

which vary in various substances;
depending on their density.

Being elastic, explains how sound - radiating from a source -
carries
or spreads around corners, and through orifices, where it spreads
out
again.

Light is considered to consist of "longitudinal waves",

Wrong. Light is "tranverse waves". Look it up.

each being an
entity in itself something like this ~~~~~ so that light radiates -
from a source - radially in straight lines; but not being elastic,
these rays of light don't readily spread around corners or after
passing through orifices;

Ah but they do. The spreading of the waves has to do with the
relative
size of the orifice to the wavelength of the wave. Visible light
waves
have a *much* smaller wavelength than audible sound waves. This is
the
*only* reason for the difference in the behavior. If you make an
orifice that is comparable in size to the light wave, then the
spreading becomes just as dramatic as sound waves.

except as they may reflect from other
surfaces.

The squiggly nature, wave length or phase pattern of light rays
have
a
unique attribute

Wrong. It is not unique. The same phenomenon occurs with sound, which
is why you can get dead spots with a stereo if you have a poorly
designed room for sound.

in that when passing through certain double slits, and
prisms, the wave length or phase pattern of the emerging rays is
altered

Wrong again. The wavelength is not altered by passing through the
slits
or even on emerging from a prism. (In the latter case, the
wavelength
emerging from the glass is the same as the wavelength entering the
glass.)

so that they may appear as different colors, or even be
cancelled.

Has anyone any other ideas?

Don

Holy smokes, Don, there was so much crapola in that post, so many
blatantly wrong statements, I almost didn't know where to begin.

PD

Well you can begin with considering a single source of the sound or
light: Are you considering a single point source, or a two point, or
diffused source?

A single point source of sound emitted radially, will diffuse and
spread throughout any elastic medium, and at a speed equal to the atoms
and molecules making up that medium; in all directions. The direction
from which the sound comes is detectable as being loudest from that
direction. Sometimes an echo will occur later, if conditions are just
right.

A single point source of light emitted in a clear medium will pass
through it practically undisturbed. Depending on the opaqueness of the
medium, the light radiation will be blocked or diminished accordingly.
Once the light passes through the medium - just a lens perhaps - it is
on its own; whether it consists of longitudinal or transverse waves; at
the speed with which it was originally emitted, because it lacks any
medium, elastic, or otherwise.

My contension is that sound is carried away from its source by the
elastic atoms and molecules that comprise all substances; and light is
carried by 'photons'; which are too small to have an elastc structure.

Elastic sound waves consist of waves of discrete elastic atoms and
molecules all bouncing around; according to the kinetic theory of
matter.

Inelastic light waves consist of waves of discrete photons, which are
too small to have an elastic structure, and have no ability to pass
around or through opaque obstacles.

I realize there is still a lot more to light than this, and I thank you
for your kind comments: I'll take them into consideration if I pursue
the subject further.

As a former 'tired bridge designer, I still consider myself somewhat of
an expert on the elasticity of particles; objects, bodies and other
masses of matter; as well as the forces and weights they exert, and/or
are exerted _upon_ them.

Don

Morituri-|-Max wrote:
"Don1" wrote in message
oups.com...

Well I hate to put a wet blanket on such a good idea; except that
it
wouldn't work! The elastic nature of sound "beams" would create a
cataclysm of sounds indistinguishable from each other: It wouldn't
be
pleasant like the inelastic beams of color reflecting off of those
many
light mirror facets on a turning central globe; that we used to
dance
to before the "dark days" of strob lights.

Don, don, don.... didn't you see PDs reply to your original post?
It is so
full of crap he almost didn't know where to start..

Why don't you learn something simple like f=ma before you start
broadcasting
more of your ignorance for all to see.

Morry, you can start by bugging off; you know less than any of us!

Don