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Re: Kinetic Energy formula check - a series of short burn rockets, and see how the velocity adds up.

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Am 11.01.2023 um 10:42 schrieb Thomas Heger:
> Am 09.01.2023 um 15:13 schrieb Joe:
> ...
>
>> Momentum is useful in particular situations, for example solving
>> problems involving snooker balls. Anything involving resonance is best
>> understood in terms of energy, as resonance is the repeated conversion
>> of one type of energy to another, and back again.
>
> My problem with momentum and energy is, that momentum is known to be a
> conserved quantity and energy assumed to be.
>
> But momentum is m*v, while kinetic energy is 1/2 *m *v².
>
> How could both quantities possibly be both conserved for the same
> object, with same mass m and same velocity v, if one curve of that
> quantity over v is linear with v and one quadratic ????
>
> If v gets smaller a little, than both curves cannot possibly coincide
> with their respective conservation curve, hence one quantity is not
> conserved, if v is altered. But we can easily alter v, because v is
> frame dependent. And choosing a different coordinate system should not
> alter the state of an object, hence neither energy nor momentum.
>

This is actually wrong, because momentum is not independent of the state 
of an object, against which a flying object hits. The velocity v is 
therefore not arbitrary and should be relative to the stationary object, 
which serves as target.

This is also the case for kinetic energy, which is also depending on the 
state of motion of a possible target.


TH

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Kinetic Energy formula check - a series of short burn rockets, and see how the velocity adds up. Dave <dwickford@yahoo.com> - 2023-01-08 09:36 +0000
  Re: Kinetic Energy formula check - a series of short burn rockets, and see how the velocity adds up. Dave <dwickford@yahoo.com> - 2023-01-08 10:13 +0000
  Re: Kinetic Energy formula check - a series of short burn rockets, and see how the velocity adds up. Jim Pennino <jimp@gonzo.specsol.net> - 2023-01-08 08:16 -0800
  Re: Kinetic Energy formula check - a series of short burn rockets, and   see how the velocity adds up. Thomas Heger <ttt_heg@web.de> - 2023-01-09 09:07 +0100
    Re: Kinetic Energy formula check - a series of short burn rockets, and   see how the velocity adds up. Joe <joe@jretrading.com> - 2023-01-09 14:13 +0000
      Re: Kinetic Energy formula check - a series of short burn rockets,   and   see how the velocity adds up. Thomas Heger <ttt_heg@web.de> - 2023-01-11 10:42 +0100
        Re: Kinetic Energy formula check - a series of short burn rockets,     and   see how the velocity adds up. Thomas Heger <ttt_heg@web.de> - 2023-01-11 11:22 +0100
      Re: Kinetic Energy formula check - a series of short burn rockets,   and   see how the velocity adds up. Thomas Heger <ttt_heg@web.de> - 2023-01-12 08:31 +0100
        Re: Kinetic Energy formula check - a series of short burn rockets,   and   see how the velocity adds up. Evangelista Barzetti <magm@hyojmkib.vi> - 2023-01-12 16:45 +0000
        Re: Kinetic Energy formula check - a series of short burn rockets,   and   see how the velocity adds up. Otto Fiscella <tfit@tiselelc.it> - 2023-01-12 16:51 +0000
          Re: Kinetic Energy formula check - a series of short burn rockets,     and   see how the velocity adds up. Thomas Heger <ttt_heg@web.de> - 2023-01-13 08:23 +0100
            Re: Kinetic Energy formula check - a series of short burn rockets, and see how the velocity adds up. Tom Roberts <tjoberts137@sbcglobal.net> - 2023-01-13 20:24 -0600
              Re: Kinetic Energy formula check - a series of short burn rockets, and see how the velocity adds up. Thomas Heger <ttt_heg@web.de> - 2023-01-14 10:00 +0100
                Re: Kinetic Energy formula check - a series of short burn rockets, and see how the velocity adds up. Faustino Biondo <uinn@bfotboia.nt> - 2023-01-25 19:19 +0000
                Re: Kinetic Energy formula check - a series of short burn rockets,   and see how the velocity adds up. Thomas Heger <ttt_heg@web.de> - 2023-01-26 09:53 +0100
                Re: Kinetic Energy formula check - a series of short burn rockets, and see how the velocity adds up. Baldomero De filippis <ppbo@ibsldimp.sn> - 2023-01-26 21:36 +0000
                Re: Kinetic Energy formula check - a series of short burn rockets,   and see how the velocity adds up. Baldomero De filippis <ppbo@ibsldimp.sn> - 2023-01-26 22:20 +0000
                Re: Kinetic Energy formula check - a series of short burn rockets,     and see how the velocity adds up. Thomas Heger <ttt_heg@web.de> - 2023-01-27 08:08 +0100
                Re: Kinetic Energy formula check - a series of short burn rockets, and see how the velocity adds up. Volney <volney@invalid.invalid> - 2023-01-27 20:23 -0500
                Re: Kinetic Energy formula check - a series of short burn rockets,   and see how the velocity adds up. Baldomero De filippis <ppbo@ibsldimp.sn> - 2023-01-26 22:34 +0000
                Re: Kinetic Energy formula check - a series of short burn rockets, and see how the velocity adds up. De filippis <ppbo@ibsldimp.snBaldomero> - 2023-01-27 21:30 +0000
  Re: Kinetic Energy formula check - a series of short burn rockets, and see how the velocity adds up. Y A <angel0000000010000000000000@gmail.com> - 2023-01-09 06:15 -0800
  Re: Kinetic Energy formula check - a series of short burn rockets, and see how the velocity adds up. Sylvia Else <sylvia@email.invalid> - 2023-01-28 09:01 +1100
    Re: Kinetic Energy formula check - a series of short burn rockets, and see how the velocity adds up. James McGinn <jimmcginn9@gmail.com> - 2023-01-29 10:50 -0800
      Re: Kinetic Energy formula check - a series of short burn rockets, and see how the velocity adds up. Jim Pennino <jimp@gonzo.specsol.net> - 2023-01-29 11:05 -0800
      Re: Kinetic Energy formula check - a series of short burn rockets, and see how the velocity adds up. Sylvia Else <sylvia@email.invalid> - 2023-01-30 22:57 +1100
  Re: Kinetic Energy formula check - a series of short burn rockets, and see how the velocity adds up. Arindam Banerjee <banerjeeadda1234@gmail.com> - 2023-01-27 23:25 -0800
    Re: Kinetic Energy formula check - a series of short burn rockets, and see how the velocity adds up. Jim Pennino <jimp@gonzo.specsol.net> - 2023-01-28 06:37 -0800
      Re: Kinetic Energy formula check - a series of short burn rockets, and see how the velocity adds up. Arindam Banerjee <banerjeeadda1234@gmail.com> - 2023-01-29 07:05 -0800
        Re: Kinetic Energy formula check - a series of short burn rockets, and see how the velocity adds up. Jim Pennino <jimp@gonzo.specsol.net> - 2023-01-29 07:50 -0800
          Re: Kinetic Energy formula check - a series of short burn rockets, and see how the velocity adds up. Arindam Banerjee <banerjeeadda1234@gmail.com> - 2023-01-29 23:10 -0800
            Re: Kinetic Energy formula check - a series of short burn rockets, and see how the velocity adds up. Jim Pennino <jimp@gonzo.specsol.net> - 2023-01-30 05:57 -0800

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