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Dr. Slick August 21st 03 09:52 AM

wrote in message ...
"Dr. Slick" wrote:

So then that would be Work = 2*pi*(radius**2)*force.

Right. But it's a bit strange with rotational work, because if
you do one rotation, you are essentially back where you started. I
believe this has something to do with the fact that the rotational
displacement is dimensionless, and linear displacement is in units of
length.


If it takes one newton to make a block move and I push it north 1
metre, then east 1 metre, then south 1 metre, then west 1 metre,
I am back where I started but I did 4 joules worth of work (but
probably not useful work).


Ok, this is what i meant, "usefull work".


If I push the same block in a circle of radius 1 metre then I do
2pi joules of work: the circumference (distance travelled) times
the force.

So the expression at the top should not have a square in it.

...Keith


Nope. It needs another radius term...one for the circumference,
and one for the moment arm.


Slick

[email protected] August 21st 03 12:41 PM

wrote:

Please think carefully about your reply.

Energy = Force x Distance

When I push the block in a square pattern, the distance is the sum of
the sides of the square.

When I push the block in a circle, the distance is the circumference,
which is 2 x pi x Radius.

If, after reviewing the above, you still think the radius needs
squaring, please explain why the equation for energy when pushing
in a circle is different than that for pushing in a square.

As an exercise, consider pushing in a triangle pattern, a square
pattern, pentagon, hexagon, heptagon, octagon, ....

Each pattern above is getting closer and closer to being a circle;
at which pattern does the equation for Energy change from being
the distance moved to being twice the enclosed area?


And I forgot to say...

In a rotary system, it is often deemed convenient to think of Distance
in terms of rotations or angular displacement.

Torque is just a way of thinking about Force so that you can use
angular displacement instead of distance.

....Keith

Richard Harrison August 21st 03 01:51 PM

Dr. Slick wrote:
"And if the permittivity (impedance) of the material surrounding an
antenna will affect its input impedance, I think it is something to
consider."

The permittivity surrounding our antennas rarely changes and is the same
for nearly all antennas.

My dictionary says of permittivity: "See Dielectric Constant".

Velocity can be affected by dielectric constant as is seen in
solid-dielectric coax. Fortunately, the dielectric constant of the
environment our antennas operate in is nearly constant.

Were matching antennas to 377 ohms significant, it would manifest itself
in the century of experience of using many antennas of many differing
types.

Best regards, Richard Harrison, KB5WZI


Dr. Slick August 21st 03 05:30 PM

wrote in message ...
Please think carefully about your reply.


I always do, unless i hafta take a dump! hehe..



Energy = Force x Distance

When I push the block in a square pattern, the distance is the sum of
the sides of the square.

When I push the block in a circle, the distance is the circumference,
which is 2 x pi x Radius.

If, after reviewing the above, you still think the radius needs
squaring, please explain why the equation for energy when pushing
in a circle is different than that for pushing in a square.

As an exercise, consider pushing in a triangle pattern, a square
pattern, pentagon, hexagon, heptagon, octagon, ....

Each pattern above is getting closer and closer to being a circle;
at which pattern does the equation for Energy change from being
the distance moved to being twice the enclosed area?

...Keith


It looks like you are correct. Sorry for the mistake, it's been
too
long since i've done a torque problem! I'm more of a EE!


Look at this page:

http://www.sinclair.net/~ddavis/170_ps10.html


If you agree that torque is in units of N*m, then according to this
page, you have to multiply this by the angular displacement, which
will be 2*pi for a full revolution. I was incorrectly trying to
multiple by the actual circumference traveled, which is incorrect
because we want angular displacement instead.

To me, this kinda shows how torque is closer to work than just
force, because with torque, you just need to and the angular
displacement (dimensionless) to get the work done.

Thanks for the review, Keith.


Slick

Richard Clark August 21st 03 05:48 PM

On Thu, 21 Aug 2003 06:31:45 -0400, wrote:


As an exercise, consider pushing in a triangle pattern, a square
pattern, pentagon, hexagon, heptagon, octagon, ....

Each pattern above is getting closer and closer to being a circle;
at which pattern does the equation for Energy change from being
the distance moved to being twice the enclosed area?

...Keith


Hi All,

Just what purpose do the two of you think you are achieving with
Torque and boxing the compass?

73's
Richard Clark, KB7QHC

Tdonaly August 21st 03 07:46 PM


Hi All,

Just what purpose do the two of you think you are achieving with
Torque and boxing the compass?

73's
Richard Clark, KB7QHC


Circle squarers are ten times worse than flat-earthers,
turtles or not.
73,
Tom Donaly, KA6RUH

Richard Clark August 22nd 03 03:35 AM

On Tue, 19 Aug 2003 14:47:58 -0700, Roy Lewallen
wrote:

I find this most interesting. As a P.E. licensed by the state of Oregon
(since 1981), I'm aware that I'm subject to state laws governing the
code of conduct of Professional Engineers, and all other applicable
state laws. I didn't realize that I had legal obligations to NIST, or
that any other federal agency has requirements for P.E.s of all states.
Would you please provide some reference where I can further research
this obligation and the rules it has imposed that I'm legally required
to comply with?

Roy Lewallen, W7EL, P.E.


Hi Roy,

"RCW 19.94.150
Standards recognized.
The system of weights and measures in customary use in the United
States and the metric system of weights and measures are jointly
recognized, and either one or both of these systems shall be used
for all commercial purposes in this state. The definitions of
basic units of weight and measure and weights and measures
equivalents, as published by the national institute of standards
and technology or any successor organization, are recognized and
shall govern weighing or measuring instruments or devices used in
commercial activities and other transactions involving weights and
measures within this state."

This is from the state of Washington, I will leave it to you to
research your own particular point of liability in Oregon.

I would add what the IEEE offers into the matter of observing
standards in the development of software and confirming your
disclaimers with:

"The Legal Standard of Professionalism"

"One curious fact from the legal perspective decries a serious
lack: there is no such thing as software malpractice. Why?
A peek into the legal mind provides a disturbing explanation.
There is insufficient evidence to show that programmers
know how to learn from each other, much less from the rest of
the world."

I, for one, could envision you having interest in both, but as I
stated before, I could not see you bothered with the first - seeing
that you have not volunteered any additional details of your trade
aside from software, that stands to good reason.

73's
Richard Clark, KB7QHC

Roy Lewallen August 22nd 03 04:03 AM

Richard Clark wrote:
On Tue, 19 Aug 2003 14:47:58 -0700, Roy Lewallen
wrote:


I find this most interesting. As a P.E. licensed by the state of Oregon
(since 1981), I'm aware that I'm subject to state laws governing the
code of conduct of Professional Engineers, and all other applicable
state laws. I didn't realize that I had legal obligations to NIST, or
that any other federal agency has requirements for P.E.s of all states.
Would you please provide some reference where I can further research
this obligation and the rules it has imposed that I'm legally required
to comply with?

Roy Lewallen, W7EL, P.E.



Hi Roy,

"RCW 19.94.150
Standards recognized.
The system of weights and measures in customary use in the United
States and the metric system of weights and measures are jointly
recognized, and either one or both of these systems shall be used
for all commercial purposes in this state. The definitions of
basic units of weight and measure and weights and measures
equivalents, as published by the national institute of standards
and technology or any successor organization, are recognized and
shall govern weighing or measuring instruments or devices used in
commercial activities and other transactions involving weights and
measures within this state."

This is from the state of Washington, I will leave it to you to
research your own particular point of liability in Oregon.


Wow, thanks for the heads-up. I'll be more careful to specify circuit
board trace line widths in furlongs, and volumes of radar detection
regions in bushels, those being duly recognized customary units of
measure here in Oregon. I'll no longer use lakj;ofs and mapeurqak!pys,
which I had previously been using.

I would add what the IEEE offers into the matter of observing
standards in the development of software and confirming your
disclaimers with:

"The Legal Standard of Professionalism"

"One curious fact from the legal perspective decries a serious
lack: there is no such thing as software malpractice. Why?
A peek into the legal mind provides a disturbing explanation.
There is insufficient evidence to show that programmers
know how to learn from each other, much less from the rest of
the world."

I, for one, could envision you having interest in both, but as I
stated before, I could not see you bothered with the first - seeing
that you have not volunteered any additional details of your trade
aside from software, that stands to good reason.


As I'm afraid so often happens with your postings, I haven't a clue what
you're trying to say. It sounds vaguely like a complaint, but I can't
for the life of me fathom what about, except that it seems to be some
sort of objection to the legal disclaimers which accompany my software.
Could you please try to rephrase it in a way that can be understood by
an engineer with a sadly deficient liberal arts education?

If you feel that the legal disclaimers which accompany my software are
unduly restrictive or otherwise too onerous for you, or you're not fully
satisfied with EZNEC in any way, all you need do is so state in
peasant-level plain language so I can understand it, and I'll promptly
refund the full purchase price. Just as it says clearly in the EZNEC
manual (Help/Contents/Introduction/Guarantee).

Roy Lewallen, W7EL


Richard Clark August 22nd 03 04:25 AM

On Thu, 21 Aug 2003 20:03:41 -0700, Roy Lewallen
wrote:

Richard Clark wrote:
On Tue, 19 Aug 2003 14:47:58 -0700, Roy Lewallen
wrote:


I find this most interesting. As a P.E. licensed by the state of Oregon
(since 1981), I'm aware that I'm subject to state laws governing the
code of conduct of Professional Engineers, and all other applicable
state laws. I didn't realize that I had legal obligations to NIST, or
that any other federal agency has requirements for P.E.s of all states.
Would you please provide some reference where I can further research
this obligation and the rules it has imposed that I'm legally required
to comply with?

Roy Lewallen, W7EL, P.E.



Hi Roy,

"RCW 19.94.150
Standards recognized.
The system of weights and measures in customary use in the United
States and the metric system of weights and measures are jointly
recognized, and either one or both of these systems shall be used
for all commercial purposes in this state. The definitions of
basic units of weight and measure and weights and measures
equivalents, as published by the national institute of standards
and technology or any successor organization, are recognized and
shall govern weighing or measuring instruments or devices used in
commercial activities and other transactions involving weights and
measures within this state."

This is from the state of Washington, I will leave it to you to
research your own particular point of liability in Oregon.


Wow, thanks for the heads-up. I'll be more careful to specify circuit
board trace line widths in furlongs, and volumes of radar detection
regions in bushels, those being duly recognized customary units of
measure here in Oregon. I'll no longer use lakj;ofs and mapeurqak!pys,
which I had previously been using.


Uh-huh.

....
Could you please try to rephrase it in a way that can be understood by
an engineer with a sadly deficient liberal arts education?


Hi Roy,

Probably not.

73's
Richard Clark, KB7QHC

Roy Lewallen August 22nd 03 04:49 AM

Richard Clark wrote:
On Thu, 21 Aug 2003 20:03:41 -0700, Roy Lewallen
wrote:
...

Could you please try to rephrase it in a way that can be understood by
an engineer with a sadly deficient liberal arts education?



Hi Roy,

Probably not.

73's
Richard Clark, KB7QHC


Surely, then, one of the more educated but earthy readers understood it
and can translate for me. Anyone? Here it is again in case it was missed
the first time:

----- Text to translate:

I would add what the IEEE offers into the matter of observing
standards in the development of software and confirming your
disclaimers with:

"The Legal Standard of Professionalism"

"One curious fact from the legal perspective decries a serious
lack: there is no such thing as software malpractice. Why?
A peek into the legal mind provides a disturbing explanation.
There is insufficient evidence to show that programmers
know how to learn from each other, much less from the rest of
the world."

I, for one, could envision you having interest in both, but as I
stated before, I could not see you bothered with the first - seeing
that you have not volunteered any additional details of your trade
aside from software, that stands to good reason.

------

What's the point? Can someone clue me in?

Roy Lewallen, W7EL



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