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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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#626799 — Precession

Let's discuss precession.
Does a toy top have precession?

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#626812

On 4/4/2017 9:01 AM, john wrote:
> Let's discuss precession.
> Does a toy top have precession?
>

only when it has angular velocity of rotation (AVR)

it also has nutation, either pure, free or Euler kind.

    anything else I can help you with?

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#626824

oh, really?

> it also has nutation, either pure, free or Euler kind.
> 
>     anything else I can help you with?

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#626818

john <johnsefton288@gmail.com> writes:

>Let's discuss precession.
>Does a toy top have precession?

Obsessive.compulsive disorder (OCD) is a mental disorder where people feel 
the need to check things repeatedly, perform certain routines repeatedly 
(called "rituals"), or have certain thoughts repeatedly. People are unable 
to control either the thoughts or the activities for more than a short 
period of time.
...

https://en.wikipedia.org/wiki/Obsessive%E2%80%93compulsive_disorder

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#626826

On 4/4/2017 9:01 AM, john wrote:
> Let's discuss precession.
> Does a toy top have precession?
>

Yes, it does. Did you know that a toy top in the Space Station will not 
precess? Wonder why?

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

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#626848

Odd
"

Yes, it does. Did you know that a toy top in the Space Station will not 
precess? Wonder why? 
"
No Gravity?
So, in no Gravity, a top never falls over?

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#626850

On 4/4/2017 12:41 PM, john wrote:
> Odd
> "
>
> Yes, it does. Did you know that a toy top in the Space Station will not
> precess? Wonder why?
> "
> No Gravity?

Well, there is gravity up at the Space Station. It's only down a few 
percent from surface gravity. But the station is in free-fall. So 
gravity becomes non-apparent, just like if you were in a freely falling 
elevator on the surface of the earth, or an airplane in free fall.

> So, in no Gravity, a top never falls over?

In no gravity, no, a top never falls over because there's no "down". 
More importantly, it never PRECESSES. Because there is no external 
gravity to provide the torque.


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

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#626870

On 4/4/2017 12:45 PM, Odd Bodkin wrote:
> On 4/4/2017 12:41 PM, john wrote:
>> Odd
>> "
>>
>> Yes, it does. Did you know that a toy top in the Space Station will not
>> precess? Wonder why?
>> "
>> No Gravity?

> Well, there is gravity up at the Space Station. It's only down a few
> percent from surface gravity. But the station is in free-fall. So
> gravity becomes non-apparent, just like if you were in a freely falling
> elevator on the surface of the earth, or an airplane in free fall.
>
>> So, in no Gravity, a top never falls over?
>
> In no gravity, no, a top never falls over because there's no "down".
> More importantly, it never PRECESSES. Because there is no external
> gravity to provide the torque.
>
>

"a top only falls if it is torqued off. "

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#627110

Odd
"

In no gravity, no, a top never falls over because there's no "down". 
More importantly, it never PRECESSES. Because there is no external 
gravity to provide the torque. 
"
In no Gravity, will a spinning top resist having
it's plane of spin changed?
And will that resistance change with frequency 
of rotation?

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#627111

On 4/5/2017 9:59 AM, john wrote:
> Odd
> "
>
> In no gravity, no, a top never falls over because there's no "down".
> More importantly, it never PRECESSES. Because there is no external
> gravity to provide the torque.
> "
> In no Gravity, will a spinning top resist having
> it's plane of spin changed?

Yes, it still will be a gyroscope.

> And will that resistance change with frequency
> of rotation?

If you mean by resistance that the application of a given torque will 
result in less of a change in the direction of the axis of rotation, the 
answer is yes. Note that you won't see anything about this until a 
torque is applied.


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

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#627120

Odd
"

If you mean by resistance that the application of a given torque will 
result in less of a change in the direction of the axis of rotation, the 
answer is yes. Note that you won't see anything about this until a 
torque is applied. "

Perfect.
So a certain amount of energy will be
required to change the plane of rotation
a certain amount.
Then the spinning thing will remain spinning
in that new plane?
And if it is spinning faster, it will take
more energy to get it to that new plane?
-

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#627124

On 4/5/2017 12:10 PM, john wrote:
> Odd
> "
>
> If you mean by resistance that the application of a given torque will
> result in less of a change in the direction of the axis of rotation, the
> answer is yes. Note that you won't see anything about this until a
> torque is applied. "
>
> Perfect.
> So a certain amount of energy will be
> required to change the plane of rotation
> a certain amount.

There will be work expended by that external torque, yes.

> Then the spinning thing will remain spinning
> in that new plane?

If the torque is removed, yes. If the torque remains, then the direction 
of the axis will continue to change.

> And if it is spinning faster, it will take
> more energy to get it to that new plane?

Not necessarily. If the top is spinning faster, you can exert the same 
torque, expend the same work, and get to the same new orientation of the 
axis. It will just take longer. If you want it to get to the new 
orientation just as quickly, then you will need a larger torque.


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

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#627192

Odd
"
If the torque is removed, yes. If the torque remains, then the direction 
of the axis will continue to change. 

"

So, can we agree that spinning things
have zero precession by default?
And they resist any change in their state
more strongly, the faster they spin?

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#627409

Odd
"" 
If the torque is removed, yes. If the torque remains, then the direction 
of the axis will continue to change. 

" 

So, can we agree that spinning things 
have zero precession by default? 
And they resist any change in their state 
more strongly, the faster they spin? 

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#627411

On 4/5/2017 6:36 PM, john wrote:
> Odd
> "
> If the torque is removed, yes. If the torque remains, then the direction
> of the axis will continue to change.
>
> "
>
> So, can we agree that spinning things
> have zero precession by default?

I don't know what "default" means to you. The presence of precession has 
to do with the presence and direction of an external torque.

> And they resist any change in their state
> more strongly, the faster they spin?

The phrase "their state" is too loose. If you mean that the change in 
angular momentum is reduced, the faster they spin, the answer is no. If 
you mean that the rate of precession is decreased, the answer is yes.


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

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#627417

Odd
"On 4/5/2017 6:36 PM, john wrote: 
> Odd 
> " 
> If the torque is removed, yes. If the torque remains, then the direction 
> of the axis will continue to change. 
> 
> " 
> 
> So, can we agree that spinning things 
> have zero precession by default? 

I don't know what "default" means to you. The presence of precession has 
to do with the presence and direction of an external torque. "
Is the resistance to precession
still there, with no torque?

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#627420

On 4/6/2017 11:18 AM, john wrote:
> Odd
> "On 4/5/2017 6:36 PM, john wrote:
>> Odd
>> "
>> If the torque is removed, yes. If the torque remains, then the direction
>> of the axis will continue to change.
>>
>> "
>>
>> So, can we agree that spinning things
>> have zero precession by default?
>
> I don't know what "default" means to you. The presence of precession has
> to do with the presence and direction of an external torque. "
> Is the resistance to precession
> still there, with no torque?
>

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

It's like the mass of an object out in space, John. It has mass, but the 
only way you can tell how much it has is by trying to apply a force to it.

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

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#627426

On Thursday, April 6, 2017 at 9:36:41 AM UTC-7, Odd Bodkin wrote:
> On 4/6/2017 11:18 AM, john wrote:
> > Odd
> > "On 4/5/2017 6:36 PM, john wrote:
> >> Odd
> >> "
> >> If the torque is removed, yes. If the torque remains, then the direction
> >> of the axis will continue to change.
> >>
> >> "
> >>
> >> So, can we agree that spinning things
> >> have zero precession by default?
> >
> > I don't know what "default" means to you. The presence of precession has
> > to do with the presence and direction of an external torque. "
> > Is the resistance to precession
> > still there, with no torque?
> >
> 
> There's no way to tell, without apply a torque.
> 
> It's like the mass of an object out in space, John. It has mass, but the 
> only way you can tell how much it has is by trying to apply a force to it.
> 
> -- 
> Odd Bodkin -- maker of fine toys, tools, tables

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#627433

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?

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#627438

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.

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

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