Sujet : Re: Bicycle physics question
De : <bp (at) *nospam* www.zefox.net>
Groupes : rec.bicycles.techDate : 25. Jun 2024, 20:49:56
Autres entêtes
Organisation : A noiseless patient Spider
Message-ID : <v5f3gk$1lugk$2@dont-email.me>
References : 1 2 3 4 5 6
User-Agent : tin/2.6.2-20221225 ("Pittyvaich") (FreeBSD/14.0-RELEASE-p6 (arm64))
bp@
www.zefox.net wrote:
AMuzi <am@yellowjersey.org> wrote:
That all seems right to me, assuming CG means distance to
tire contact and not height.
The potential energy represented by the bike is the work
needed to raise the bike's CG against the force of gravity.
PE is mass times gravity times height measured along gravity,
not along the bike..
>
Perhaps this is my first mistake: On a balanced bicycle, apparent
gravity _is_ along the bike.
Part of what makes the problem confusing is that the rider
is in a non-inertial frame, leaning and turning along with
slowing down and speeding up. That may be confusing my
senses
>
Thinking the matter over, it seems likely I'm simply mistaken
in posing the question. The only dissipative mechanism is friction,
the largest sources being air resistance and tire rolling/scrubbing
friction. I suppose one could argue there has to be a
small speedup in the front of the bike, since it travels a longer
path in a curve than the rear and so must gain some speed, but that's
miniscule relative to the bike.
In the end, my perception of "pedaling out" of a turn is mostly an
artifact of my own senses.... or, perhaps, imagination.
Sorry for the bother, thanks for writing!
bob prohaska