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Precession

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  Precession john <johnsefton288@gmail.com> - 2017-04-04 07:01 -0700
    Re: Precession Serg io <invalid@invalid.com> - 2017-04-04 10:07 -0500
      Re: Precession noTthaTguY <abu.kuanysh05@gmail.com> - 2017-04-04 08:45 -0700
    Re: Precession moroney@world.std.spaamtrap.com (Michael Moroney) - 2017-04-04 15:27 +0000
    Re: Precession Odd Bodkin <bodkinodd@gmail.com> - 2017-04-04 10:49 -0500
      Re: Precession john <johnsefton288@gmail.com> - 2017-04-04 10:41 -0700
        Re: Precession Odd Bodkin <bodkinodd@gmail.com> - 2017-04-04 12:45 -0500
          Re: Precession Serg io <invalid@invalid.com> - 2017-04-04 14:32 -0500
          Re: Precession john <johnsefton288@gmail.com> - 2017-04-05 07:59 -0700
            Re: Precession Odd Bodkin <bodkinodd@gmail.com> - 2017-04-05 10:30 -0500
              Re: Precession john <johnsefton288@gmail.com> - 2017-04-05 10:10 -0700
                Re: Precession Odd Bodkin <bodkinodd@gmail.com> - 2017-04-05 12:23 -0500
                  Re: Precession john <johnsefton288@gmail.com> - 2017-04-05 16:36 -0700
                    Re: Precession john <johnsefton288@gmail.com> - 2017-04-06 07:02 -0700
                    Re: Precession Odd Bodkin <bodkinodd@gmail.com> - 2017-04-06 09:19 -0500
                      Re: Precession john <johnsefton288@gmail.com> - 2017-04-06 09:18 -0700
                        Re: Precession Odd Bodkin <bodkinodd@gmail.com> - 2017-04-06 11:36 -0500
                          Re: Precession "reber G=emc^2" <herbertglazier0@gmail.com> - 2017-04-06 10:26 -0700
                          Re: Precession john <johnsefton288@gmail.com> - 2017-04-06 11:17 -0700
                            Re: Precession Odd Bodkin <bodkinodd@gmail.com> - 2017-04-06 13:45 -0500
                              Re: Precession john <johnsefton288@gmail.com> - 2017-04-06 12:07 -0700
                                Re: Precession Odd Bodkin <bodkinodd@gmail.com> - 2017-04-06 14:31 -0500
                                  Re: Precession pnalsing@gmail.com - 2017-04-06 15:06 -0700
                                Re: Precession john <johnsefton288@gmail.com> - 2017-04-06 12:32 -0700
                                  Re: Precession Odd Bodkin <bodkinodd@gmail.com> - 2017-04-06 14:46 -0500
                                Re: Precession benj <nobody@gmail.com> - 2017-04-06 20:23 -0400
                                Re: Precession moroney@world.std.spaamtrap.com (Michael Moroney) - 2017-04-07 03:51 +0000
                                  Re: Precession john <johnsefton288@gmail.com> - 2017-04-07 06:40 -0700
                                    Re: Precession Odd Bodkin <bodkinodd@gmail.com> - 2017-04-07 08:53 -0500
                                      Re: Precession john <johnsefton288@gmail.com> - 2017-04-07 07:38 -0700
                                        Re: Precession Odd Bodkin <bodkinodd@gmail.com> - 2017-04-07 09:58 -0500
                                        Re: Precession john <johnsefton288@gmail.com> - 2017-04-07 07:58 -0700
                                          Re: Precession Odd Bodkin <bodkinodd@gmail.com> - 2017-04-07 10:00 -0500
                                            Re: Precession Odd Bodkin <bodkinodd@gmail.com> - 2017-04-07 10:02 -0500
                                          Re: Precession moroney@world.std.spaamtrap.com (Michael Moroney) - 2017-04-07 15:32 +0000
                                    Re: Precession moroney@world.std.spaamtrap.com (Michael Moroney) - 2017-04-07 18:04 +0000
                              Re: Precession benj <nobody@gmail.com> - 2017-04-06 20:22 -0400
                            Re: Precession moroney@world.std.spaamtrap.com (Michael Moroney) - 2017-04-07 03:50 +0000
                              Re: Precession noTthaTguY <abu.kuanysh05@gmail.com> - 2017-04-07 19:41 -0700
                                Re: Precession noTthaTguY <abu.kuanysh05@gmail.com> - 2017-04-07 20:21 -0700
    Re: Precession Edward Prochak <edprochak@gmail.com> - 2017-04-04 11:38 -0700
    Re: Precession "reber G=emc^2" <herbertglazier0@gmail.com> - 2017-04-06 10:25 -0700
    Re: Precession Odd Bodkin <bodkinodd@gmail.com> - 2017-04-07 14:32 -0500

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#627440

Odd
"A spinning object will resist having its spin axis changed, and the .."
Okay.
Question.
Why, according to your understanding of science,
does this happen?

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#627444

On 4/6/2017 2:07 PM, john wrote:
> Odd
> "A spinning object will resist having its spin axis changed, and the .."
> Okay.
> Question.
> Why, according to your understanding of science,
> does this happen?
>

Newton's 2nd law says F = dp/dt. This is shorthand for saying that if 
you apply a force, then the momentum will experience a change such that 
the *change* (not the new momentum, but the change) is in the direction 
of the force, and the rate of that change is given by the size of the force.

Newton's 2nd law for rotation says T = dL/dt. This is shorthand for 
saying that if you apply a torque, then the angular momentum will 
experience a change such that the *change* (not the new angular 
momentum, but the change) is in the direction of the torque, and the 
rate of that change is given by the size of the torque.

(Hopefully, you can see why physicists would much rather use T=dL/dt 
than all those words, because that short equation carries all the same 
information as all those words. Why you would refuse to learn 
mathematics is beyond me.)

I could show you a very simple demonstration of how this works with a 
spinning bicycle wheel whose axle is held up at one end with a rope. I 
could show you the direction of the angular momentum and the size of it. 
I could show you the direction of the torque. This would also then show 
you the direction of the *change* in the angular momentum. This would 
then make it clear which way the angular momentum would have to swing. 
Then you would see it actually swing this way, in what's called 
precession. Then I would increase the spin of the bike wheel, making the 
angular momentum bigger. Then you'd see that the same *change* in 
angular momentum applied to a bigger angular momentum results in a 
slower swing. But it's SO much easier to show this to you in a 
demonstration than it is with words that I'm not going to elaborate the 
words further.

-- 
Odd Bodkin -- maker of fine toys, tools, tables

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#627475

On Thursday, April 6, 2017 at 12:31:52 PM UTC-7, Odd Bodkin wrote:
> On 4/6/2017 2:07 PM, john wrote:
> > Odd
> > "A spinning object will resist having its spin axis changed, and the .."
> > Okay.
> > Question.
> > Why, according to your understanding of science,
> > does this happen?
> >
> 
> Newton's 2nd law says F = dp/dt. This is shorthand for saying that if 
> you apply a force, then the momentum will experience a change such that 
> the *change* (not the new momentum, but the change) is in the direction 
> of the force, and the rate of that change is given by the size of the force.
> 
> Newton's 2nd law for rotation says T = dL/dt. This is shorthand for 
> saying that if you apply a torque, then the angular momentum will 
> experience a change such that the *change* (not the new angular 
> momentum, but the change) is in the direction of the torque, and the 
> rate of that change is given by the size of the torque.
> 
> (Hopefully, you can see why physicists would much rather use T=dL/dt 
> than all those words, because that short equation carries all the same 
> information as all those words. Why you would refuse to learn 
> mathematics is beyond me.)
> 
> I could show you a very simple demonstration of how this works with a 
> spinning bicycle wheel whose axle is held up at one end with a rope. I 
> could show you the direction of the angular momentum and the size of it. 
> I could show you the direction of the torque. This would also then show 
> you the direction of the *change* in the angular momentum. This would 
> then make it clear which way the angular momentum would have to swing. 
> Then you would see it actually swing this way, in what's called 
> precession. Then I would increase the spin of the bike wheel, making the 
> angular momentum bigger. Then you'd see that the same *change* in 
> angular momentum applied to a bigger angular momentum results in a 
> slower swing. But it's SO much easier to show this to you in a 
> demonstration than it is with words that I'm not going to elaborate the 
> words further.
> 
> -- 
> Odd Bodkin -- maker of fine toys, tools, tables

Here are a couple...

https://www.youtube.com/watch?v=8H98BgRzpOM

https://www.exploratorium.edu/snacks/bicycle-wheel-gyro

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#627445

I'll shoot first.
Resistance to precession must be the same
as Inertia- the resistance of Space itself
to have its flow-pattern changed.
The spinning object carries Space with it
and establishes a "groove". Moving against 
that groove is more difficult, the faster the
spin. Similarly, overcoming inertia is simply
setting Space in motion; establishing the
"groove".

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#627449

On 4/6/2017 2:32 PM, john wrote:
> I'll shoot first.
> Resistance to precession must be the same
> as Inertia-

Not really but close. There's a reason that "inertia" is so 
loosey-goosey a concept in physics that it is rarely used in a careful 
presentation.

Resistance to precession is a statement of conservation of angular 
momentum, which is exactly analogous to conservation of linear momentum.

If you want to know why momentum and angular momentum are conserved, it 
has to do with the symmetry of the laws of physics for different places 
you sit or different directions you're facing.

Your babble below is not right, and I would suggest you stick with what 
is really known, rather than veering too quickly away to babble 
something "new".

> the resistance of Space itself
> to have its flow-pattern changed.
> The spinning object carries Space with it
> and establishes a "groove". Moving against
> that groove is more difficult, the faster the
> spin. Similarly, overcoming inertia is simply
> setting Space in motion; establishing the
> "groove".
>


-- 
Odd Bodkin -- maker of fine toys, tools, tables

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#627520

On 04/06/2017 03:07 PM, john wrote:
> Odd
> "A spinning object will resist having its spin axis changed, and the .."
> Okay.
> Question.
> Why, according to your understanding of science,
> does this happen?
>
Because the text books all say it does...tee hee!

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#627557

john <johnsefton288@gmail.com> writes:

>Odd
>"A spinning object will resist having its spin axis changed, and the .."
>Okay.
>Question.
>Why, according to your understanding of science,
>does this happen?

Conservation of angular momentum.

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#627597

MM
"
>Why, according to your understanding of science, 
>does this happen? 

Conservation of angular momentum. "

Why is it conserved?
What physically happens?

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#627598

On 4/7/2017 8:40 AM, john wrote:
> MM
> "
>> Why, according to your understanding of science,
>> does this happen?
>
> Conservation of angular momentum. "
>
> Why is it conserved?
> What physically happens?
>

Conservation of momentum is a law of physics that stems from the 
symmetry in the universe that all laws of physics are the same here as 
they are over there.

I should explain something here. The root cause of why things behave the 
way they do is this set of laws. You are looking for a physical 
mechanism that explains how things work, you should be aware that every 
physical mechanism that you can think of (gears, ropes, pulleys, 
bouncing balls) all do what they do because of underlying laws of physics.

Gears for example do what they do BECAUSE OF Newton's 2nd law for 
rotation and conservation of angular momentum. If those laws did not 
hold, gears would not work. ALL simple machines work on the basis of 
physical laws.

You focus on the moving parts. But you have not figured out that the 
moving parts work because of the physical laws. Learn the laws UNDER the 
moving parts, and you start to understand how things work.

-- 
Odd Bodkin -- maker of fine toys, tools, tables

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#627599

Odd
"laws. 

You focus on the moving parts. But you have not figured out that the 
moving parts work because of the physical laws. Learn the laws UNDER the "

Laws?
There is physical structure of matter
and there is physical structure of "space".

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#627600

On 4/7/2017 9:38 AM, john wrote:
> Odd
> "laws.
>
> You focus on the moving parts. But you have not figured out that the
> moving parts work because of the physical laws. Learn the laws UNDER the "
>
> Laws?

Yes, laws.

> There is physical structure of matter
> and there is physical structure of "space".

Physical structure of matter does not explain how a pulley works. 
Newton's laws of motion do. Physical structure of matter does not 
explain how a lever works. Conservation of energy does.

You are focused on the wrong thing for finding the explanation. The 
explanation does not rest on the moving parts or the structure. The 
explanation rests on the laws.


-- 
Odd Bodkin -- maker of fine toys, tools, tables

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#627601

You elucidate the physical structure of Space,
and the "laws" become obvious. Space is
Fractal, in structure. This means that what
appears to us to be nothing is actually the
same energy that makes up our matter/atoms,
but in much finer increments. It is
like a fluid made from super-fine material.
When something
rotates through repeatedly, it sets up a flow in
Space. Just like a well-traveled path in the bush,
it is much easier to go with the flow.
Laws result from structure. You deny structure.

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#627602

On 4/7/2017 9:58 AM, john wrote:
> You elucidate the physical structure of Space,
> and the "laws" become obvious.

Sorry, John, but no, you have it wrong. The laws explain the structure.
You have it flipped.

Do you understand why a lever works? It's VERY easy to explain using 
conservation of energy.

I know you don't WANT to learn about laws, because you like just the 
parts. But the laws are really where it's at.

> Space is
> Fractal, in structure. This means that what
> appears to us to be nothing is actually the
> same energy that makes up our matter/atoms,
> but in much finer increments. It is
> like a fluid made from super-fine material.
> When something
> rotates through repeatedly, it sets up a flow in
> Space. Just like a well-traveled path in the bush,
> it is much easier to go with the flow.
> Laws result from structure. You deny structure.
>


-- 
Odd Bodkin -- maker of fine toys, tools, tables

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#627603

On 4/7/2017 10:00 AM, Odd Bodkin wrote:
> On 4/7/2017 9:58 AM, john wrote:
>> You elucidate the physical structure of Space,
>> and the "laws" become obvious.
>
> Sorry, John, but no, you have it wrong. The laws explain the structure.
> You have it flipped.
>
> Do you understand why a lever works? It's VERY easy to explain using
> conservation of energy.

More importantly, I would challenge you to explain how a lever works by 
just using the structure. Go ahead and try.

>
> I know you don't WANT to learn about laws, because you like just the
> parts. But the laws are really where it's at.
>
>> Space is
>> Fractal, in structure. This means that what
>> appears to us to be nothing is actually the
>> same energy that makes up our matter/atoms,
>> but in much finer increments. It is
>> like a fluid made from super-fine material.
>> When something
>> rotates through repeatedly, it sets up a flow in
>> Space. Just like a well-traveled path in the bush,
>> it is much easier to go with the flow.
>> Laws result from structure. You deny structure.
>>
>
>


-- 
Odd Bodkin -- maker of fine toys, tools, tables

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#627618

john <johnsefton288@gmail.com> writes:

<snip blather>

Are you trying to learn or just want to blather your
nonsense here?

The laws of physics determine why matter and energy behave
the way they do, and can answer many of your questions if
you just try.

Things like F=ma (force = mass * acceleration) tells you
things like if you apply an unbalanced force to a mass, it
will accelerate at a known rate.

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#627650

john <johnsefton288@gmail.com> writes:

>MM
>"
>>Why, according to your understanding of science, 
>>does this happen? 

>Conservation of angular momentum. "

>Why is it conserved?
>What physically happens?

It can be derived from the fact that linear momentum is conserved,
but that has a bunch of math that I doubt that you care about.

It can also be derived by the laws of physics being the same
everywhere, specifically the fact that the laws of physics are
the same no matter which way you are facing (rotational symmetry).
Again, more messy math, read Noether's Theorem if you are interested
in such stuff.

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#627519

On 04/06/2017 02:45 PM, Odd Bodkin wrote:
> On 4/6/2017 1:17 PM, john wrote:
>> Odd
>> "There's no way to tell, without apply a torque. "
>>
>> So. A spinning object has a resistance to
>> having its precession changed from 0
>> to some other value.
>> This can be proven by applying a torque.
>> Okay?
>>
>
> Not quite right, but close.
>
> A spinning object will resist having its spin axis changed, and the
> degree of resistance can be discovered by applying a torque in a
> direction other than the axis direction.
>
> If the torque continues to be applied in such a way that its orientation
> relative to the spin axis stays the same, then this change in the spin
> axis is called precession.

Precession is the secret of alien anti-gravity drive, odd. A gyro will 
defy gravity and hang out in space held up by unknown forces! I learned 
this with the gyroscope I was given as a kid. That is on the money.

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#627556

(I probably shouldn't be feeding the OCD monster, but...)

john <johnsefton288@gmail.com> writes:

>Odd
>"There's no way to tell, without apply a torque. "

>So. A spinning object has a resistance to
>having its precession changed from 0
>to some other value.
>This can be proven by applying a torque.
>Okay?

You need to look up the terms moment of inertia, torque, angular momentum
and angular velocity, and how these properties all relate to each other.

Specifically, angular momentum, like linear monentum, is a conserved 
quantity.  Meaning it cannot be created or destroyed, just transferred
from one object to another via torque.

Angular momentum has both a quantity and a direction, again like linear
momentum.  The direction is indicated by a vector in the direction of
the rotation axis.

Precession is essentially a constant change in angular momentum.  The 
magnitude remains the same but the vector direction constantly changes.

To change the direction (the angular momentum), you need a torque.  With
no torque, no precession.  With no torque, a spinning object will continue
spinning with the same magnitude and direction, like the earth. *
I keep trying to tell you this but you keep blowing me off.

Now crack a book and get reading!

(*) Yes the earth's rotation is slowing ever so slightly and it does 
precess just a little bit, but this is from torques from the gravitational
effects of the sun and the moon.

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#627720

guess that he's never held a spinning bicycle wheel
by the quickrelease -- wild speculation!

> Precession is essentially a constant change in angular momentum.  The 
> magnitude remains the same but the vector direction constantly changes.
> 
> To change the direction (the angular momentum), you need a torque.  With
> no torque, no precession.  With no torque, a spinning object will continue
> spinning with the same magnitude and direction, like the earth.
> (*) Yes the earth's rotation is slowing ever so slightly and it does 
> precess just a little bit, but this is from torques from the gravitational
> effects of the sun and the moon.

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#627725

only variable is counter\closckwise

> guess that he's never held a spinning bicycle wheel
> by the quickrelease -- wild speculation!
> 
> > Precession is essentially a constant change in angular momentum.  The 
> > magnitude remains the same but the vector direction constantly changes.

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