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From: Luigi Fortunati <fortunati.luigi@gmail.com>
Newsgroups: sci.physics.research
Subject: Re: The rope
Date: Mon, 26 May 2025 21:54:25 PDT
Organization: A noiseless patient Spider
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Approved: Jonathan Thornburg [remove -color to reply]" <dr.j.thornburg@gmail-pink.com (sci.physics.research)
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Jonathan Thornburg [remove -color to reply] il 25/05/2025 09:53:48 ha 
scritto:
> ...
> The key distinction is that Newton was referring to a situation where
> the rope is treated as massless, with no forces acting on it except for
> the pulls (tension) at each end.  
> ...

It's not a fundamental distinction and Newton never said it.

In any case, regardless of what Newton said (or didn't say), the 
absence of mass doesn't change anything I wrote

The rope has no mass? Okay, it has no mass.

Are you saying that there are two tensions at the ends of the rope? Of 
course there are!

On one side there is the tension caused by the force of the horse and 
on the other there is the tension caused by the force of the stone.

The horse pulls the rope forward (action) and generates its tension, 
the stone pulls backwards (reaction) and generates the other tension.

The rope (with or without mass) is in the middle and must move 
accordingly: if the horse pulls more the rope *must* accelerate 
forwards, if it pulls more the stone *must* accelerate backwards, if 
they pull equally it cannot accelerate.

So just look at how the rope moves to understand if the action wins or 
if the reaction wins or if they are equal.

Luigi Fortunati