Date: Wed, 22 May 2002 10:33:58 -0500

Author: Gary Karshner

Subject: RE: Cenco Spring

Post:

Karl,
Your correct. Try a little experiment and compare one hanging
large end at the top to one with the small end at the top and note the
spacing of the coils. Small end up all the coils are separated where as
large end up the are not. When oscillating large end up the coils can
collide and make a real mess of change in period with mass measurements.

Gary

At 04:02 PM 5/21/02 -0500, you wrote:
>The narrow end has a slightly greater k value for its stiffness due to the
>tighter spiral. This means it can support more weight per delta y
>elongation than the more openly wound end. Hopefully, this difference in
>the k value, as you go along the length of the spring, is just enought to
>compensate for the "extra weight" of the next turn of the coil immediately
>below it, then the next 2 turns, then the next 3 turns, and so on, until
>you reach the top. Karl
>
> >We have some springs like these and our lab manual tells the students to
> >hang them
> >with the narrow end up. Why?
> >I know the freq. will be slightly different the other way, but is there
> >any reason to
> >choose narrow end up rather than narrow end down?
>
>Dr. Karl I. Trappe Desk (512) 471-4152
>Lecture Demonstration Office Office (512) 471-5411
>Physics Department, Mail Stop C-1600 Home (512) 264-1616
>The University of Texas at Austin
>Austin, Texas 78712-1081

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