Re: Plucked strings

[Bob Sciamanda <trebor@VELOCITY.NET>]

I have a MathCad program which shows exactly this behavior of a plucked
string.  The program does an FFT of the initial shape and then develops
and sums the Fourier components in time.  It was written in MathCad 6Plus,
but is only a few statements (FFT is built into MathCad) and is easily
transported to other programs.  In MathCad the time series of frames can
either be shown individually or (using a built-in animation routine) shown
as a "movie" with choosable time scale.
If anyone is interested I can e-mail this program as an attachment.

Bob

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

----- Original Message -----
From: "William Beaty" <billb@ESKIMO.COM>
To: <PHYS-L@lists.nau.edu>
Sent: Monday, July 03, 2000 4:31 PM
Subject: Plucked strings
> . . .
> I remember seeing frames from high-speed movie of a plucked string a
> couple of years ago.  . . The movie of the plucked string looked
something like this below.  Note
> the odd "flat top" of the string's shape which grows and shrinks.
> . . .
> Initial position
>                 __--__
>             __--      --__
>         __--              --__
>     __--                      --__
> __--                              --__
>
>
>
>
> 2nd frame
>             __----------__
>         __--              --__
>     __--                      --__
> __--                              --__
>
>
>
>
> 3rd
>         __------------------__
>     __--                      --__
> __--                              --__
>
>
>
> 4th
>
>     __--------------------------__
> __--                              --__
>
>
>
>
> 5th
>
> __---------------------------------__
>
>
>
>
> 6th
> __                                 __
>   ---------------------------------
>
>
>
> 7th
> __                                  __
>   --__                          __--
>       --------------------------
>
>
>
> 8th
> __                                  __
>   --__                          __--
>       --__                  __--
>           ------------------
>
>
> 9th
> __                                  __
>   --__                          __--
>       --__                  __--
>           --__          __--
>               --__  __--
>                   --
>
>  . . .
((((((((((((((((((((( ( (  (   (    (O)    )   )  ) ) ))))))))))))))))))))
)
> William J. Beaty                                  SCIENCE HOBBYIST
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> billb@eskimo.com                                  http://www.amasci.com
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