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Re: How you can tell if someone is really interested in physics

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On 3/28/2022 4:46 PM, Odd Bodkin wrote:
> whodat <whodaat@void.nowgre.com> wrote:
>> On 3/28/2022 8:09 AM, Odd Bodkin wrote:
>>> kenseto <setoken@att.net> wrote:
>>>> On Saturday, March 26, 2022 at 10:07:57 AM UTC-4, bodk...@gmail.com wrote:
>>>>> kenseto <set...@att.net> wrote:
>>>>>> On Saturday, March 26, 2022 at 9:13:28 AM UTC-4, bodk...@gmail.com wrote:
>>>>>>> kenseto <set...@att.net> wrote:
>>>>>>>> On Friday, March 25, 2022 at 9:46:27 PM UTC-4, Paul Alsing wrote:
>>>>>>>>> On Friday, March 25, 2022 at 6:32:28 PM UTC-7, kenseto wrote:
>>>>>>>>>
>>>>>>>>>> High school physics is wrong when it and you assert that a single
>>>>>>>>>> attractive force can make an object go around in circles. It cannot.
>>>>>>>>> And your evidence to support this claim is what, exactly?
>>>>>>>>
>>>>>>>> Hey stupid , a single attractive force can only cause an object to go
>>>>>>>> in a straight line.
>>>>>>> Newton says otherwise. other
>>>>>>>
>>>>>> Newton is wrong
>>>>> Well done, fruitcake.
>>>>>
>>>> Hey stupid: Launching a satellite requires a force to make it go vertically.
>>>> Then it requires another force making to go horizontally.
>>>> The combination of these two forces making the satellite  to follow a
>>>> curved orbital path.
>>>> Gee you are so fucking stupid.
>>>
>>> In Newtonian mechanics, Ken, the change in motion of a body is determined
>>> by the forces that are acting on it AT THAT INSTANT. Not the forces that
>>> were exerted on it a minute ago, an hour ago, a year ago. This is the
>>> content of F=ma.
>>>
>>> After the stone has been dropped by the bird, the forces the bird used to
>>> lift the stone are irrelevant because the bird is no longer in contact with
>>> the stone. Now the ONLY force acting on the stone is gravity.
>>>
>>> After the rocket engine has stopped firing, the force on the satellite is
>>> gravity and gravity alone, because what the rocket engine did an hour ago
>>> is irrelevant now.
>>
>>
>> In that case, how did the state called "initial conditions" occur?
> 
> In the case of Newtonian mechanics, which is described by a 2nd order
> differential equation in the position vector, the initial conditions are
> the position and first derivative of position at the boundary, commonly
> taken to be (but not necessarily) t=0.
> 
> The history of all that preceded is irrelevant.
> 
> This you can check directly by seeing that a golf-swing, where the
> club-ball impact ceases before t=0, gets the same result as launching the
> same ball from a long descending chute with a small up-ramp where contact
> ceases before t=0, gets the same result as a buried rail gun where
> departure from the gun is just before t=0 —- just as long as the ball’s
> position and derivative of position have the same values (same initial
> conditions) at t=0. None of the details of the forces used to produce those
> initial conditions at t=0 have the slightest impact on what happens after
> t=0, when the ball is governed by one force only.

Mumbo-jumbo. (Potentially) all sorts of forces went into creating the
initial conditions that you prize so highly. The treatment (dismissal)
of those forces is (perhaps) a mathematician's wet dream. This is an
example where the process adapted by a discipline takes precedent over
the factual events. I don't side with the cranks in this, but refuse
your ilk credit. Yes, initial condition is critical to understanding
motion. One cannot ignore how that initial condition was achieved for
the convenience of momentary analysis.

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Re: How you can tell if someone is really interested in physics kenseto <setoken@att.net> - 2022-03-23 07:46 -0700
  Re: How you can tell if someone is really interested in physics Odd Bodkin <bodkinodd@gmail.com> - 2022-03-23 15:23 +0000
    Re: How you can tell if someone is really interested in physics kenseto <setoken@att.net> - 2022-03-24 05:40 -0700
      Re: How you can tell if someone is really interested in physics Odd Bodkin <bodkinodd@gmail.com> - 2022-03-24 13:55 +0000
        Re: How you can tell if someone is really interested in physics Maciej Wozniak <maluwozniak@gmail.com> - 2022-03-24 09:03 -0700
        Re: How you can tell if someone is really interested in physics kenseto <setoken@att.net> - 2022-03-25 06:46 -0700
          Re: How you can tell if someone is really interested in physics Odd Bodkin <bodkinodd@gmail.com> - 2022-03-25 15:11 +0000
            Re: How you can tell if someone is really interested in physics kenseto <setoken@att.net> - 2022-03-25 18:32 -0700
              Re: How you can tell if someone is really interested in physics Paul Alsing <pnalsing@gmail.com> - 2022-03-25 18:46 -0700
                Re: How you can tell if someone is really interested in physics kenseto <setoken@att.net> - 2022-03-26 05:59 -0700
                Re: How you can tell if someone is really interested in physics Odd Bodkin <bodkinodd@gmail.com> - 2022-03-26 13:13 +0000
                Re: How you can tell if someone is really interested in physics kenseto <setoken@att.net> - 2022-03-26 06:39 -0700
                Re: How you can tell if someone is really interested in physics Odd Bodkin <bodkinodd@gmail.com> - 2022-03-26 14:07 +0000
                Re: How you can tell if someone is really interested in physics kenseto <setoken@att.net> - 2022-03-27 08:02 -0700
                Re: How you can tell if someone is really interested in physics Odd Bodkin <bodkinodd@gmail.com> - 2022-03-28 13:09 +0000
                Re: How you can tell if someone is really interested in physics whodat <whodaat@void.nowgre.com> - 2022-03-28 16:32 -0500
                Re: How you can tell if someone is really interested in physics Odd Bodkin <bodkinodd@gmail.com> - 2022-03-28 21:46 +0000
                Re: How you can tell if someone is really interested in physics whodat <whodaat@void.nowgre.com> - 2022-03-29 09:34 -0500
                Re: How you can tell if someone is really interested in physics Odd Bodkin <bodkinodd@gmail.com> - 2022-03-29 17:52 +0000
                Re: How you can tell if someone is really interested in physics Russ Diaz <rdi@urvndm.mx> - 2022-03-26 13:45 +0000
              Re: How you can tell if someone is really interested in physics Odd Bodkin <bodkinodd@gmail.com> - 2022-03-26 01:55 +0000
          Re: How you can tell if someone is really interested in physics Michael Moroney <moroney@world.std.spaamtrap.com> - 2022-03-25 15:20 -0400
            Re: How you can tell if someone is really interested in physics kenseto <setoken@att.net> - 2022-03-26 05:48 -0700
              Re: How you can tell if someone is really interested in physics Michael Moroney <moroney@world.std.spaamtrap.com> - 2022-03-26 16:53 -0400
                Re: How you can tell if someone is really interested in physics Maciej Wozniak <maluwozniak@gmail.com> - 2022-03-26 21:30 -0700
        Re: How you can tell if someone is really interested in physics kenseto <setoken@att.net> - 2022-03-25 07:34 -0700

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