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Re: Meditations about the force

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Paul B. Andersen alle ore 14:00:31 del 19/08/2017 ha scritto:
> Acceleration is what an accelerometer measures.
> When you are stationary on the ground, the accelerometer
> says you are accelerating vertically upwards at 9.8 m/s.

It is 9.8 m/s^2 and not 9.8 m/ s.

> In free fall, the accelerometer shows that your acceleration is zero.
>
> The only thing that can accelerate you, is a real force
> that is acting on you. When you are sitting on a chair,
> there is a real force pushing your butt. This force is
> measurable, and you can feel it. You are accelerating
> according to F = mg. F can easily be measured with a scale.

You said it well: this "strength" is measurable!

Your accelerometer is nothing more than a dynamometer that measures 
forces and not acceleration!

So much so that both me and the chair I sit on are firm and do not 
accelerate.

Between us there is only the strength of the chair (pushing me upwards) 
and the strength of my reaction (pushing the chair down).

Or vice versa, which is the same (strength and reaction are 
interchangeable).

And this is the "strength" that the accelerometer measures.

> In free fall, no force is acting on you, so you are
> not accelerating.

It is obvious that in the free fall the accelerometer does not measure 
any strength because I do not force against anything (there is nothing 
against me) and because gravity does not force against me (even I 
oppose it) !

Opposition only occurs when I crash on the ground and then there is the 
force and the accelerometer is the measure!

Before that fatal moment, I can only know the acceleration by measuring 
the variation in the speed with which Earth approaches me.

-- 
Luigi Fortunati

Credere e' piu' facile che pensare
Believing is easier than thinking

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Thread

Meditations about the force Luigi Fortunati <fortunati.luigi@gmail.com> - 2017-08-15 17:50 +0200
  Re: Meditations about the force Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-08-16 01:34 +0200
    Re: Meditations about the force mlwozniak@wp.pl - 2017-08-15 23:34 -0700
      Re: Meditations about the force Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-08-19 12:52 +0200
        Re: Meditations about the force Séverin Thibault <ruud@bwiu.ei> - 2017-08-19 11:04 +0000
        Re: Meditations about the force mlwozniak@wp.pl - 2017-08-19 10:43 -0700
    Re: Meditations about the force Luigi Fortunati <fortunati.luigi@gmail.com> - 2017-08-18 10:10 +0200
      Re: Meditations about the force mlwozniak@wp.pl - 2017-08-18 01:32 -0700
      Re: Meditations about the force Dirk Van de moortel <dirkvandemoortel@hotspam.not> - 2017-08-18 15:06 +0200
      Re: Meditations about the force Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-08-18 15:56 +0200
        Re: Meditations about the force mlwozniak@wp.pl - 2017-08-18 07:06 -0700
      Re: Meditations about the force "Paul B. Andersen" <relativity@paulba.no> - 2017-08-19 14:00 +0200
        Re: Meditations about the force Luigi Fortunati <fortunati.luigi@gmail.com> - 2017-08-19 17:45 +0200
          Re: Meditations about the force Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-08-19 21:28 +0200
        Re: Meditations about the force mlwozniak@wp.pl - 2017-08-19 10:44 -0700
        Re: Meditations about the force Thomas Heger <ttt_heg@web.de> - 2017-08-19 20:19 +0200
          Re: Meditations about the force Séverin Thibault <ruud@bwiu.ei> - 2017-08-19 19:56 +0000
            Re: Meditations about the force Séverin Thibault <ruud@bwiu.ei> - 2017-08-19 20:00 +0000

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