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Re: Momentum, energy and angular momentum cannot be created or destroyed

From Sergio <invalid@invalid.com>
Newsgroups sci.physics
Subject Re: Momentum, energy and angular momentum cannot be created or destroyed
Date 2016-03-31 16:03 -0500
Organization Aioe.org NNTP Server
Message-ID <ndk3br$ren$1@gioia.aioe.org> (permalink)
References <ZJadnYw_CMkg92DLnZ2dnUU7-YOdnZ2d@giganews.com> <ndjtc7$has$1@gioia.aioe.org> <ndjupf$ce3$1@dont-email.me>

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On 3/31/2016 2:49 PM, Poutnik wrote:
> Dne 31/03/2016 v 21:21 Sergio napsal(a):
>> On 3/31/2016 1:21 PM, Sam Wormley wrote:
>>> Momentum, energy and angular momentum cannot be created or destroyed
>>
>>>>
>>>> This can be stated simply, "Momentum, energy and angular momentum
>>>> cannot be created or destroyed."
>>
>> hold on,
>>
>> momentum and angular momentum are vectors, energy is not.
>
> Yes, but it is not relevant.

seems like the units would have to match

>
>>
>> also each of the above can be changed into other forms, and into heat,
>> which is both created and destroyed.
>>
>
> Could you illustrate how any of above
> can be changed to the other ones ?
>
>

bow and arrow,
arrow flies to hit blade on wind direction indicator rotating it around, 
  (arrow stopped)
so linear momentum transformed into angular momentum rotation of wind 
indicator, with friction losses.

lots of other examples, linear to angular .

also it seems Energy should include both kinetic and potential.


and Energy can be dispersed so  widely it is hard to measure, therefore 
can be considered destroyed.  guess there is a time factor in that 
somewhere too



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Thread

Momentum, energy and angular momentum cannot be created or destroyed Sam Wormley <swormley1@gmail.com> - 2016-03-31 13:21 -0500
  Re: Momentum, energy and angular momentum cannot be created or destroyed jimp@specsol.spam.sux.com - 2016-03-31 18:33 +0000
  Re: Momentum, energy and angular momentum cannot be created or destroyed Sergio <invalid@invalid.com> - 2016-03-31 14:21 -0500
    Re: Momentum, energy and angular momentum cannot be created or destroyed Poutnik <poutnik4nntp@gmail.com> - 2016-03-31 21:49 +0200
      Re: Momentum, energy and angular momentum cannot be created or destroyed Sergio <invalid@invalid.com> - 2016-03-31 16:03 -0500
        Re: Momentum, energy and angular momentum cannot be created or destroyed Poutnik <poutnik4nntp@gmail.com> - 2016-04-01 07:49 +0200
        Re: Momentum, energy and angular momentum cannot be created or destroyed Timo <timo@physics.uq.edu.au> - 2016-04-01 01:14 -0700

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