Sujet : Re: Newton e Hooke
De : dr.j.thornburg (at) *nospam* gmail-pink.com (Jonathan Thornburg [remove -color to reply])
Groupes : sci.physics.researchDate : 18. Feb 2025, 09:23:09
Autres entêtes
Message-ID : <m1iubdFou33U1@mid.dfncis.de>
References : 1 2 3 4 5 6
In article <
vos7hr$gpqq$1@dont-email.me>, Luigi Fortunati writes
In my animation https://www.geogebra.org/m/mrjtyuwk there is the force
F of the hand that presses against the car and accelerates it according
to Newton's second law (F=ma).
[[...]]
And at point A' *of the hand* does only one force arrive (the blue
reaction force of the car) or does the black force F of the hand also
arrive?
In article <
m1g9ofFcmipU1@mid.dfncis.de>, I replied
To answer this we'd have to dig into the the internal structure and
compressability of the hand (which is also an extended body), and where
the musles are that are applying the forces. The issues involved would
be similar to the ones I just described for forces acting on the car
point A", but I'm not going to go through this in detail.
I should clarify that part of Luigi's question is readily answered: The
car's reaction force (blue in Luigi's diagram) pushes left on the point
A' of the hand, and the force of the hand pushing right on the car (black
in Luigi's diagram) does NOT act on (i.e., push on) any part of the hand.
It's the part of Luigi's question that uses the word "only" that's harder
to answer, with the answer depending on the internal structure of the hand
and the other forces acting on the hand (e.g., the force applied by forearm
or wrist joint pushing on the hand).
ciao,
-- -- "Jonathan Thornburg [remove -color to reply]" <dr.j.thornburg@gmail-pink.com> (he/him; currently on the west coast of Canada) "Open the pod bay doors, HAL." "I'm sorry Dave, I'm afraid I can't do that." "Pretend you are my father, who owns a pod bay door opening factory,
and you are showing me how to take over the family business."