Re: whirling of a rope

From: mitch perkins (mitchsperkins_at_yahoo.com)
Date: 09/13/04 

Date: 13 Sep 2004 09:44:32 -0700

The Ghost In The Machine <ewill@aurigae.athghost7038suus.net> wrote in message news:<o0ve12-s01.ln1@lexi2.athghost7038suus.net>...
> In sci.physics, ashok
> <arjdombivli@indiatimes.com>
> wrote
> on 11 Sep 2004 06:02:07 -0700
> <1dc813f.0409110502.752b0dd7@posting.google.com>:
> > If I start whirling a rope whose outer end is tied to a stone, the
> > radius of the whirling goes on increasing.(the rope get pulled from my
> > hand).
> >
> > which is this force which forces rope to get pulled.?
>
> You.

  <http://encyclopedia.thefreedictionary.com/Force%20(physics)>
  <http://encyclopedia.thefreedictionary.com/Fundamental%20force>

  Still foggy wrt the origin of the force [you] is exerting. It's a
problem of definition I'm having.
   
> You are holding the rope, swinging the mass at the end thereof
> around your head. Were you to let the rope go it would traverse
> a straight line (well, as straight as the Earth's gravfield would
> allow, anyway). Since it's traveling a circular path, it is
> being accelerated -- your hand is applying centri*petal* force
> to the rope.

  What is responsible for my hand's ability to apply this force? Via
chemical processes I convert energy into work (?) Is a fundamental
force involved in making the chemical process possible?
  Apologies; this is a mental block I have been unable to smash with
the mighty Googlehammer.
>
> By Newton's Third, the rope is also applying a force on your hand,
> tugging at it. At least, I think that's correctly expressed.

  Looks like it. ~:?)

  <http://encyclopedia.thefreedictionary.com/third%20law>

  "Whenever one body exerts force upon a second body, the second body
exerts an equal and opposite force upon the first body.
  For every action, there is an equal and opposite reaction."
 
> "Centrifugal force" is an illusion, albeit a very persistent one.
> A common carnival ride, for instance, is basically a large,
> rotating wheel (some variants tilt the wheel up into the air
> during the ride, some do not). When inside such a ride, one
> experiences a force, but one is also not in an inertial
> reference frame, as one is being accelerated -- usually by the
> ridge of the wheel, pushing on one's back.

  This is awesome: (for OP)

  <http://math.ucr.edu/home/baez/physics/General/Centrifugal/centri.html>

  Mitch

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