Re: "Negotiating" a curve. EUREKA?

[Bob Sciamanda <trebor@VELOCITY.NET>]

The effect I mentioned in my last post is real, but not, at lest
ordinarily, a major effect, alone.  It wouldn't turn you on ice!  Keep
thinking!  Going out now.

Bob

Bob Sciamanda (W3NLV)
Physics, Edinboro Univ of PA (em)
trebor@velocity.net
http://www.velocity.net/~trebor

----- Original Message -----
From: Ludwik Kowalski <KowalskiL@MAIL.MONTCLAIR.EDU>
To: <PHYS-L@lists.nau.edu>
Sent: Saturday, November 06, 1999 4:35 PM
Subject: Re: "Negotiating" a curve. EUREKA?


> Hi Bob:
>
> In the spirit of an extreme possible simplification, but
> without taking away the essentials, one may consider
> two identical tricycles with locked steering columns.
> One with the front wheel parallel to the y axis and
> another with the front wheel turned to the left by 10
> degrees. The initial velocities are identical at time zero.
>
> John_D would probably say (and I was saying the
> same thing the other night) that forces in the bearing
> are internal and that only external forces matter. This
> would certainly be the case if the wheels were locked.
> Then I realized that wheels are not rigid and that the
> FBD can not be used, except for the rigid platform.
> I have to think about the situation again. Reading the
> books recommended by Leigh will be the first step.
> Regards, Ludwik
>
> Bob Sciamanda wrote:
>
> > Ludwik,
> > It occurred to me (while walking the Lake Erie beach) that the wheel
> > communicates/interacts with the cycle frame, not only through the
> > horizontal axle bearings, but also through the (almost) vertical
steering
> > column bearings.  In addition, the wheel interacts with you (the
rider)
> > through the handlebar/yoke/steering column system.  In particular,
when
> > you turn the wheel for a left turn, your body will turn in the
opposite
> > direction about the steering column; this forces you toward the center
of
> > curvature and also makes you lean in that direction.  Think on it.
> > ( Note that this is not appealing to any "gyroscopic" effects - what I
> > describe happens, in principle, even if the wheel is not rotating.)