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JAXAshby September 1st 04 12:43 PM

the function becomes
more like a square root function, which is mathematically definately not an
asymptote.

Meindert


watch it, Meindert. dougies is now going to spend two days and five posts
trying to show *you* are wrong when you say a square function is no asymptotic.

DSK September 1st 04 01:04 PM

Meindert Sprang wrote:
These figures are not realistic. Up to the point of the hull speed they
resemble reality, but as soon as the hull starts planing, more 'ordinary'
rules of resistance/drag apply and as far as I know the function becomes
more like a square root function, which is mathematically definately not an
asymptote.


Well, there's your mistake. A hull under planing conditions is subject
to normal drag, including air resistance. It no longer is subject to
wave-making resistance, but that doesn't mean that *all* resistance goes
away. And the function for increase is a multiple of velocity squared,
which will have an asymptote.

DSK


JAXAshby September 1st 04 01:31 PM

See Meindert? I told you dougies would be claiming that a square function is
asymptotic. even when dougies was handed the definition of the word you
_still_ can't figure out what it means and he _still_ tries to prove that a
concrete slab salesman selling to first-time single wide buyers is a genius at
math.

From: DSK
Date: 9/1/2004 8:04 AM Eastern Daylight Time
Message-id:

Meindert Sprang wrote:
These figures are not realistic. Up to the point of the hull speed they
resemble reality, but as soon as the hull starts planing, more 'ordinary'
rules of resistance/drag apply and as far as I know the function becomes
more like a square root function, which is mathematically definately not an
asymptote.


Well, there's your mistake. A hull under planing conditions is subject
to normal drag, including air resistance. It no longer is subject to
wave-making resistance, but that doesn't mean that *all* resistance goes
away. And the function for increase is a multiple of velocity squared,
which will have an asymptote.

DSK










Meindert Sprang September 1st 04 03:26 PM

"DSK" wrote in message
.. .
Well, there's your mistake. A hull under planing conditions is subject
to normal drag, including air resistance. It no longer is subject to
wave-making resistance, but that doesn't mean that *all* resistance goes
away. And the function for increase is a multiple of velocity squared,
which will have an asymptote.


Ok, I'm going to argue this one only once: by mathematical definition, a
squared function is NOT asymptotic. Because, as you can read in any
mathematics book, an asymptote reaches infinity on one axis for a defined
value on the other axis, while a squared function can reach infinity on both
axes.

Meindert
PS: thanks for the warning Jax but he was quicker than you thought.....:-)




DSK September 1st 04 05:26 PM

Meindert Sprang wrote:
Ok, I'm going to argue this one only once: by mathematical definition, a
squared function is NOT asymptotic. Because, as you can read in any
mathematics book, an asymptote reaches infinity on one axis for a defined
value on the other axis, while a squared function can reach infinity on both
axes.


Oh, OK. I see now...

Please explain further... the power/speed graph can reach infinity on
both axes? Does this mean that we can have negative horsepower? That
would make for excellent fuel efficiency!

DSK


Meindert Sprang September 1st 04 07:39 PM

"DSK" wrote in message
...
Meindert Sprang wrote:
Ok, I'm going to argue this one only once: by mathematical definition, a
squared function is NOT asymptotic. Because, as you can read in any
mathematics book, an asymptote reaches infinity on one axis for a

defined
value on the other axis, while a squared function can reach infinity on

both
axes.


Oh, OK. I see now...

Please explain further... the power/speed graph can reach infinity on
both axes? Does this mean that we can have negative horsepower? That
would make for excellent fuel efficiency!


Sigh! With both axes I mean X and Y axis. And in our case only in the first
quadrant, where X and Y are positive.

Meindert



DSK September 1st 04 07:55 PM

Please explain further... the power/speed graph can reach infinity on
both axes? Does this mean that we can have negative horsepower? That
would make for excellent fuel efficiency!



Meindert Sprang wrote:
Sigh! With both axes I mean X and Y axis. And in our case only in the first
quadrant, where X and Y are positive.


Dammit, another great idea shot down... I thought we could have a boat
where if you put the engine in gear while you were sailing, it would
actually *produce* fuel.

Anyway, the power/speed curve will "approach infinity" much much much
sooner along the power axis (usually Y) than the speed axis (usually X).
That's the whole point.

Fresh Breezes
Doug King


Brian Whatcott September 2nd 04 12:09 AM

On Wed, 01 Sep 2004 00:32:59 -0400, Rodney Myrvaagnes
wrote:

I am puzzled. What quantity approaches an asymptote and against what
independent variable?
Rodney Myrvaagnes NYC


Count me as lunatic fringe. I see planing boats every day.
What you describe is not an asymptotic relation.
Rodney Myrvaagnes J36 Gjo/a


I hold that the situation I describe, though fanciful, is aptly
called asymptotic. Telling me that my description is not asymptotic as
I describe it, is called an assertion "Ex Cathedra". How are your
ecclesiastical affiliations?

//
If on further consideration, you might allow that there is SOME upper
power and speed for a given hull, then perhaps you might even describe
the relation as asymptotic?
Brian Whatcott Altus OK


No. Unless you can show an asymptotic function (mathematical) that
describes the situation.

///
In any case it is only a metaphor.
Rodney Myrvaagnes NYC J36 Gjo/a


Let me rise to the challenge, and hopefully demetaphoricate this
mathematical concept a little more for you with a worked example, as
given at the following URL
http://www.purplemath.com/modules/asymtote4.htm

Take a look at the third worked example on this page, it carries a
numerator in the second power, and a denominator in the first power.

This is somewhat like a practical thrust versus speed relation for a
hull. You will notice there may be a vertical asymptote, a slant
asymptote or a horizontal asymptote (though not both the latter,
obviously)

Hope this helps? It may also be responsive to Meindert's view [below]:

Meindert Sprang wrote:
Ok, I'm going to argue this one only once: by mathematical definition, a
squared function is NOT asymptotic. Because, as you can read in any
mathematics book, an asymptote reaches infinity on one axis for a defined
value on the other axis, while a squared function can reach infinity on both
axes.


Brian Whatcott Altus OK

JAXAshby September 2nd 04 03:27 AM

Meindert, you confuse dougies so with facts.

Well, there's your mistake. A hull under planing conditions is subject
to normal drag, including air resistance. It no longer is subject to
wave-making resistance, but that doesn't mean that *all* resistance goes
away. And the function for increase is a multiple of velocity squared,
which will have an asymptote.


Ok, I'm going to argue this one only once: by mathematical definition, a
squared function is NOT asymptotic. Because, as you can read in any
mathematics book, an asymptote reaches infinity on one axis for a defined
value on the other axis, while a squared function can reach infinity on both
axes.

Meindert
PS: thanks for the warning Jax but he was quicker than you thought.....:-)












JAXAshby September 2nd 04 03:28 AM

give it up, dogies. you are
sooooooooooooooooooooooooooooooooooooooooooooooooo oooooooooooooooooooooooo
oooooooooooooooooooooooooooooooooooo far behind the power curve you can never
recover.

pity that you do not now and never will understand that.


From: DSK
Date: 9/1/2004 12:26 PM Eastern Daylight Time
Message-id:

Meindert Sprang wrote:
Ok, I'm going to argue this one only once: by mathematical definition, a
squared function is NOT asymptotic. Because, as you can read in any
mathematics book, an asymptote reaches infinity on one axis for a defined
value on the other axis, while a squared function can reach infinity on

both
axes.


Oh, OK. I see now...

Please explain further... the power/speed graph can reach infinity on
both axes? Does this mean that we can have negative horsepower? That
would make for excellent fuel efficiency!

DSK











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