Re: Spring Problem Revisited

["W. Barlow Newbolt" <wnewbolt@liberty.uc.wlu.edu>]

I'm not at all sure I know what is bothering you, but here goes.  It is
true the mass will not accelerated as long as it is in equilibrium, but
when you turn it loose it is not in equilibrium any more and the restoring
force due to the spring accelerates it.




On Thu, 30 Oct 1997 SSMOTHERMAN@MSCC.CC.TN.US wrote:

> 	Good answers guys, I'm starting to see the light!  But, I'm still
> bothered by something.  Let me restate the problem another way.
> 	We have a horizontal, unstretched, Hookean spring connected at one end
> to a rigid support.  At the other end, I attach a mass m resting on a
> frictionless surface.  Now, I pull to the right on MASS m (not on the spring
> itself) with force F=kx.  The spring pulls back to the left on the MASS m (not
> on me) with force F=-kx.  Now, the sum of the horizontal forces acting ON THE
> MASS is 0.  NOW, how can the MASS (not the spring itself) ever accelerate?  
> 	By the way, Donald Simanek came close to answering this in his post,
> but I'm wondering if anyone else has any insight.
>
> Thanks much,
> Steven Smotherman
> Motlow State CC
> Tullahoma, TN

W. Barlow Newbolt              540-463-8881  (telephone)
218 Howe Hall                  540-463-8884  (fax)
Washington and Lee University  newbolt.w@fs.science.wlu.edu	
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"Prediction is very difficult, especially about the future."

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