OK, I picked this up on another board,a nd seeing that Eisboch, Tom,
Gene and Larry have had dealings with this stuff. I thought I'd
present it here. It has my curiosity up as well.

I'm not up on physics, concerning this so here goes:

"I searched the web but couldn't find an answer to a simple question
which for my purposes is really a matter of curiosity. Of course,
sometimes these
kinds of questions end up teaching me the most.


Most defintions of wavelength are along the lines of the distance
between points of corresponding phase of two consecutive cycles of a
wave. I'm not
an idiot , so I understand what is a pretty
straightforward definition.


What I don't get is why the term length? I mean, they don't call the
amplitude the waveheight. I kind of think of it as a wavegap. If you
painted a big sine wave on the street and asked me how long it was,
I'd get one
of those little rolling doohickies for measuring and trace the line
through its curve. Without knowing the definition in advance, I
wouldn't think you would
be asking me the straight distance between two points of
corresponding
phase.


I ask this question because I don't understand why it's called what
it's called, not because I want to tell the experts they got it
wrong. It's bugged me for a while, so I've finally decided to take the
plunge and risk looking stupid.

Thanks in advance for any responses or links to read..."


--
Jim Carr

On Jan 15, 7:50 pm, Tim wrote:
OK, I picked this up on another board,a nd seeing that Eisboch, Tom,
Gene and Larry have had dealings with this stuff. I thought I'd
present it here. It has my curiosity up as well.

I'm not up on physics, concerning this so here goes:

"I searched the web but couldn't find an answer to a simple question
which for my purposes is really a matter of curiosity. Of course,
sometimes these
kinds of questions end up teaching me the most.

Most defintions of wavelength are along the lines of the distance
between points of corresponding phase of two consecutive cycles of a
wave. I'm not
an idiot , so I understand what is a pretty
straightforward definition.

What I don't get is why the term length? I mean, they don't call the
amplitude the waveheight. I kind of think of it as a wavegap. If you
painted a big sine wave on the street and asked me how long it was,
I'd get one
of those little rolling doohickies for measuring and trace the line
through its curve. Without knowing the definition in advance, I
wouldn't think you would
be asking me the straight distance between two points of
corresponding
phase.

I ask this question because I don't understand why it's called what
it's called, not because I want to tell the experts they got it
wrong. It's bugged me for a while, so I've finally decided to take the
plunge and risk looking stupid.

Thanks in advance for any responses or links to read..."

--
Jim Carr

It is called "length" because it truly is a length. Amplitude is not
a length but has other units, for example with sound, amplitude has
units of pressure. With light, radio waves or other electromagnetic
radiation, the amplitude is electric or magnetic field. Consider the
wavelength of your VHF which is roughly about the length of your 8'
antenna. The wavelength of the microwaves in your microwave oven is
roughly 3 cm (just over an inch). The wavelength of your cell phone
waves is somewhat longer than those in a microwave, about 3X.
Infrared light has a a wavelength as small as .5 micron or about .
00002". Visible light has length between .5 micron (red) and .3
micron (violet). Vacuum Ultraviolet goes from there down to about 120
angstroms (1 angstrom =1 X10-10 m), soft x-rays from there down to
roughly 6 angstroms and the x-rays your dentist uses down to about .6
angstroms. Gamma rays can be very short.
At the other end of the spectrum, Extremely Low Frequency waves have
lengths comparable to the diameter of the earth. Remember the old AM
radio towers, they were about the length of the AM radio waves. Your
AM radio had a long antenna cuz the AM waves were long whereas the FM
waves are much shorter hence the smaller FM antenna.
I am sure this is MUCH more than you wanted to know but AT LAST, I get
to expound on something I know something about (I make x-ray mirrors
for waves that have lengths of anywhere from 120 angstroms to 1.2
angstroms).
Now, about boats......

On Jan 15, 7:07*pm, wrote:
On Jan 15, 7:50 pm, Tim wrote:





OK, I picked this up on another board,a nd seeing that Eisboch, Tom,
Gene and Larry have had dealings with this stuff. I thought *I'd
present it here. It has my curiosity up as well.

I'm not up on physics, concerning this so here goes:

"I searched the web but couldn't find an answer to a simple question
which for my purposes is really a matter of curiosity. Of course,
sometimes these
kinds of questions end up teaching me the most.

Most defintions of wavelength are along the lines of the distance
between points of corresponding phase of two consecutive cycles of a
wave. I'm not
an idiot , so I understand what is a pretty
straightforward definition.

What I don't get is why the term length? I mean, they don't call the
amplitude the waveheight. I kind of think of it as a wavegap. If you
painted a big sine wave on the street and asked me how long it was,
I'd get one
of those little rolling doohickies for measuring and trace the line
through its curve. Without knowing the definition in advance, I
wouldn't think you would
be asking me the straight distance between two points of
corresponding
phase.

I ask this question because I don't understand why it's called what
it's called, not because I want to tell *the experts they got it
wrong. It's bugged me for a while, so I've finally decided to take the
plunge and risk looking stupid.

Thanks in advance for any responses or links to read..."

--
Jim Carr

It is called "length" because it truly is a length. *Amplitude is not
a length but has other units, for example with sound, amplitude has
units of pressure. *With light, radio waves or other electromagnetic
radiation, the amplitude is electric or magnetic field. *Consider the
wavelength of your VHF which is roughly about the length of your 8'
antenna. *The wavelength of the microwaves in your microwave oven is
roughly 3 cm (just over an inch). *The wavelength of your cell phone
waves is somewhat longer than those in a microwave, about 3X.
Infrared light has a a wavelength as small as .5 micron or about .
00002". *Visible light has length between .5 micron (red) and .3
micron (violet). *Vacuum Ultraviolet goes from there down to about 120
angstroms (1 angstrom =1 X10-10 m), soft x-rays from there down to
roughly 6 angstroms and the x-rays your dentist uses down to about .6
angstroms. *Gamma rays can be very short.
At the other end of the spectrum, Extremely Low Frequency waves have
lengths comparable to the diameter of the earth. *Remember the old AM
radio towers, they were about the length of the AM radio waves. *Your
AM radio had a long antenna cuz the AM waves were long whereas the FM
waves are much shorter hence the smaller FM antenna.
I am sure this is MUCH more than you wanted to know but AT LAST, I get
to expound on something I know something about (I make x-ray mirrors
for waves that have lengths of anywhere from 120 angstroms to 1.2
angstroms).
Now, about boats......- Hide quoted text -

- Show quoted text -

OK, about boats. handy to know whats going on when using a ship to
shore radio

?:

wrote in message
...
On Jan 15, 7:50 pm, Tim wrote:
OK, I picked this up on another board,a nd seeing that Eisboch, Tom,
Gene and Larry have had dealings with this stuff. I thought I'd
present it here. It has my curiosity up as well.

I'm not up on physics, concerning this so here goes:

"I searched the web but couldn't find an answer to a simple question
which for my purposes is really a matter of curiosity. Of course,
sometimes these
kinds of questions end up teaching me the most.

Most defintions of wavelength are along the lines of the distance
between points of corresponding phase of two consecutive cycles of a
wave. I'm not
an idiot , so I understand what is a pretty
straightforward definition.

What I don't get is why the term length? I mean, they don't call the
amplitude the waveheight. I kind of think of it as a wavegap. If you
painted a big sine wave on the street and asked me how long it was,
I'd get one
of those little rolling doohickies for measuring and trace the line
through its curve. Without knowing the definition in advance, I
wouldn't think you would
be asking me the straight distance between two points of
corresponding
phase.

I ask this question because I don't understand why it's called what
it's called, not because I want to tell the experts they got it
wrong. It's bugged me for a while, so I've finally decided to take the
plunge and risk looking stupid.

Thanks in advance for any responses or links to read..."

--
Jim Carr

It is called "length" because it truly is a length. Amplitude is not
a length but has other units, for example with sound, amplitude has
units of pressure. With light, radio waves or other electromagnetic
radiation, the amplitude is electric or magnetic field. Consider the
wavelength of your VHF which is roughly about the length of your 8'
antenna. The wavelength of the microwaves in your microwave oven is
roughly 3 cm (just over an inch). The wavelength of your cell phone
waves is somewhat longer than those in a microwave, about 3X.
Infrared light has a a wavelength as small as .5 micron or about .
00002". Visible light has length between .5 micron (red) and .3
micron (violet). Vacuum Ultraviolet goes from there down to about 120
angstroms (1 angstrom =1 X10-10 m), soft x-rays from there down to
roughly 6 angstroms and the x-rays your dentist uses down to about .6
angstroms. Gamma rays can be very short.
At the other end of the spectrum, Extremely Low Frequency waves have
lengths comparable to the diameter of the earth. Remember the old AM
radio towers, they were about the length of the AM radio waves. Your
AM radio had a long antenna cuz the AM waves were long whereas the FM
waves are much shorter hence the smaller FM antenna.
I am sure this is MUCH more than you wanted to know but AT LAST, I get
to expound on something I know something about (I make x-ray mirrors
for waves that have lengths of anywhere from 120 angstroms to 1.2
angstroms).
Now, about boats......

Can you shave in those mirrors? 8-)

BTW, good explanation.

On Jan 15, 8:33 pm, JG2U wrote:
On Tue, 15 Jan 2008 16:50:09 -0800 (PST), Tim
wrote:



OK, I picked this up on another board,a nd seeing that Eisboch, Tom,
Gene and Larry have had dealings with this stuff. I thought I'd
present it here. It has my curiosity up as well.

I'm not up on physics, concerning this so here goes:

"I searched the web but couldn't find an answer to a simple question
which for my purposes is really a matter of curiosity. Of course,
sometimes these
kinds of questions end up teaching me the most.

Most defintions of wavelength are along the lines of the distance
between points of corresponding phase of two consecutive cycles of a
wave. I'm not
an idiot , so I understand what is a pretty
straightforward definition.

What I don't get is why the term length? I mean, they don't call the
amplitude the waveheight. I kind of think of it as a wavegap. If you
painted a big sine wave on the street and asked me how long it was,
I'd get one
of those little rolling doohickies for measuring and trace the line
through its curve. Without knowing the definition in advance, I
wouldn't think you would
be asking me the straight distance between two points of
corresponding
phase.

I ask this question because I don't understand why it's called what
it's called, not because I want to tell the experts they got it
wrong. It's bugged me for a while, so I've finally decided to take the
plunge and risk looking stupid.

Thanks in advance for any responses or links to read..."

It's the distance, or "length", that the signal in question would
travel while transitioning through a complete cycle.

An audible signal will generally travel at the speed of sound, and
light (different wavelengths, different colors) will travel at the
speed of light.

Does that help?

HOWEVER, Sometimes a wave amplitude can be a length, for example a
wave on the surface of water or a wave on the surface of a drum.
Basically, these are special cases. Sorry, i forgot these obvious
examples.
The x-ray mirrors are seriously shiny but look like small cones with
holes at both ends. They are made of metal (electroformed nickel)
with an inner surface of gold. If you hold them up to the sun, they
will concentrate the sunlight like a parabolic mirror would. I'll
resist the urge to go on and on about how they work and bore you to
death.
NOW, could somebody please explain Hull Speed?

On Tue, 15 Jan 2008 16:50:09 -0800 (PST), Tim
wrote:

OK, I picked this up on another board,a nd seeing that Eisboch, Tom,
Gene and Larry have had dealings with this stuff. I thought I'd
present it here. It has my curiosity up as well.

Wavelength is the length measurement from the beginning to the end of
one full cycle. Or think of it another way, the distance a wave at a
given frequency to travel from 0 degrees to 360 degrees.

Frequency is the number of wave periods passing a point in time and is
inversely proportional to wavelength - the higher the frequency of the
signal, the shorter the wavelength.

On Tue, 15 Jan 2008 17:51:42 -0800 (PST),
wrote:

NOW, could somebody please explain Hull Speed?

We had a discussion of this a year or so ago.

As I remember, it turned heated because of the terms used - hull speed
vs speed/length ratio.

Personally, I'm neutral. :)

Personally, I'm neutral. :)

Better than being neutered! ;-)

--Mike

"Short Wave Sportfishing" wrote in message
news
On Tue, 15 Jan 2008 17:51:42 -0800 (PST),
wrote:

NOW, could somebody please explain Hull Speed?

We had a discussion of this a year or so ago.

As I remember, it turned heated because of the terms used - hull speed
vs speed/length ratio.

Personally, I'm neutral. :)

"Short Wave Sportfishing" wrote in message
...

On Tue, 15 Jan 2008 16:50:09 -0800 (PST), Tim
wrote:

OK, I picked this up on another board,a nd seeing that Eisboch, Tom,
Gene and Larry have had dealings with this stuff. I thought I'd
present it here. It has my curiosity up as well.

Wavelength is the length measurement from the beginning to the end of
one full cycle. Or think of it another way, the distance a wave at a
given frequency to travel from 0 degrees to 360 degrees.

Frequency is the number of wave periods passing a point in time and is
inversely proportional to wavelength - the higher the frequency of the
signal, the shorter the wavelength.


And by the way Tim .... the "waveform" need not be sinusoidal. It could be
a square wave, sawtooth, virtually anything.
For practical purposes to us, the wavelength is important in determining the
proper electrical length of an antenna for maximum power transfer and
resultant radiation. Ideally, the antenna would be "cut" (it's electrical
length) to the physical wavelength of the transmitting frequency, or an even
fraction of it, (i.e. 1/2 wavelength, 1/4 wavelength, 1/8, etc.)

A mismatch, meaning the antenna is electrically too short or too long,
causes out of phase "standing waves" to be set up in the antenna and/or
transmission line (coax) that is reflected back to the transmitting radio,
effectively decreasing the radio's transmitting power. The measurement of
reflected power to transmitted or "forward" power is what is referred to as
the "Standing Wave Ratio" or "SWR". In high power applications, a high
reflected standing wave can damage the radio and/or transmission line. I've
burned up transmission lines several times trying to apply high power RF
into a plasma contained in a vacuum chamber. Hate that when it happens.
It's unlikely that low power transmitters like a VHF marine radio would be
damaged (unless there was a direct short on the antenna or line) due to a
mismatch, but it *will* cut done on the effective radiated power. Your
marine radio, rated at 25 watts is actually transmitting much less,
especially if the antenna is not matched or "cut" properly.

Eisboch

On Jan 15, 8:51*pm, wrote:
On Jan 15, 8:33 pm, JG2U wrote:





On Tue, 15 Jan 2008 16:50:09 -0800 (PST), Tim
wrote:

OK, I picked this up on another board,a nd seeing that Eisboch, Tom,
Gene and Larry have had dealings with this stuff. I thought *I'd
present it here. It has my curiosity up as well.

I'm not up on physics, concerning this so here goes:

"I searched the web but couldn't find an answer to a simple question
which for my purposes is really a matter of curiosity. Of course,
sometimes these
kinds of questions end up teaching me the most.

Most defintions of wavelength are along the lines of the distance
between points of corresponding phase of two consecutive cycles of a
wave. I'm not
an idiot , so I understand what is a pretty
straightforward definition.

What I don't get is why the term length? I mean, they don't call the
amplitude the waveheight. I kind of think of it as a wavegap. If you
painted a big sine wave on the street and asked me how long it was,
I'd get one
of those little rolling doohickies for measuring and trace the line
through its curve. Without knowing the definition in advance, I
wouldn't think you would
be asking me the straight distance between two points of
corresponding
phase.

I ask this question because I don't understand why it's called what
it's called, not because I want to tell *the experts they got it
wrong. It's bugged me for a while, so I've finally decided to take the
plunge and risk looking stupid.

Thanks in advance for any responses or links to read..."

It's the distance, or "length", that the signal in question would
travel while transitioning through a complete cycle.

An audible signal will generally travel at the *speed of sound, and
light (different wavelengths, different colors) will travel at the
speed of light.

Does that help?

HOWEVER, Sometimes a wave amplitude can be a length, for example a
wave on the surface of water or a wave on the surface of a drum.
Basically, these are special cases. *Sorry, i forgot these obvious
examples.
The x-ray mirrors are seriously shiny but look like small cones with
holes at both ends. *They are made of metal (electroformed nickel)
with an inner surface of gold. *If you hold them up to the sun, they
will concentrate the sunlight like a parabolic mirror would. *I'll
resist the urge to go on and on about how they work and bore you to
death.
NOW, could somebody please explain Hull Speed?- Hide quoted text -

- Show quoted text -

Hull speed is basically the maximum speed at which a displacement type
hull can move through the water before climbing the bow wave and
planing off...