Re: [Phys-l] FW: universal gravitation lab

[Bernard Cleyet <bernardcleyet@redshift.com>]

This is all very hazy, but I did a time consuming analysis of the 
attractive force in a Cavendish and came up w/ a non-linear term.  I 
think one of the faculty agreed, but to weak to see it.  My plan was to 
replace the Leybold's glass w/ saran wrap.  My calc. indicated it was 
possible.  No time, of course.

One of the students "modelled" it as one of the exercises of the 
analogue computer lab.  At least one of the exercises was to model a 
non-linear to chaos (Rössler, or  Lonenz, etc.).  In those days digital 
was too slow, that dates me! We used X-Y recorders and an expensive Tek. 
storage scope. 

bc

p.s. in retrospect I realize all, or nearly all, the "patience" labs 
have been dropped since I retired,  Analogue, Cavendish, Brownian 
motion, etc.  Millikan is "the exception that proves the rule".  I 
replaced ones eye w/ a high sensitivity video camera and monitor.

Ken Fox wrote:

> For an IB extended essay, I had a student choose to build a replica of the
> apparatus shown in the PSSC film "Forces". He got lousy results if the goal
> was to get a good value for G. He learned a lot of Physics, however. He
> would set the apparatus to working in the middle of the night and used a
> video camera to help observe, while he went to bed!
>
> Ken Fox
>
> On 2/12/07, rgrandy@pop.mail.rice.edu <rgrandy@pop.mail.rice.edu> wrote:
>  
>
> > When I was an undergrad at Pittsburgh,  you had to do this between 2
> > am and 6 am when the street cars  (called "trolleys" or "trams"  in
> > most of the world) were not running.  I went beyond being a theorist
> > and became a philosopher.
> >
> > Richard Grandy
> > Rice University
> > Houston, TX USA
> >
> >
> >
> >    
> >
> > > Well, that's the part of real experimental physics that the simulations
> > > don't catch'  Also, the leaks in the vacuum system, the burned out
> > > electronics, and the lab assistants whose minds are elsewhere.  Some of
> > > us experience these vicissitudes early on and opt to become theorists.
> > >                              Regards,
> > >                                      Jack
> > >
> > >
> > >
> > > On Mon, 12 Feb 2007, Paul Lulai wrote:
> > >
> > >      
> > >
> > > > Man, I hated the execution of the Cavendish experiment.  Not only come
> > > > in at night *but also* try to time the buildings HVAC system to get a
> > > > good run... Arrgh.
> > > >
> > > > Paul Lulai
> > > > Physics Instructor & Online Learning Coordinator
> > > > Saint Anthony Village Senior High School, ISD 282
> > > > 3303 33rd Avenue N.E.
> > > > Saint Anthony Village, MN 55418
> > > >
> > > > (w) 612-706-1144
> > > > (fax) 612-706-1140
> > > > -----Original Message-----
> > > > From: phys-l-bounces@carnot.physics.buffalo.edu
> > > > [mailto:phys-l-bounces@carnot.physics.buffalo.edu] On Behalf Of
> > > >        
> > William
> >    
> >
> > > > Maddox
> > > > Sent: Monday, February 12, 2007 10:33 AM
> > > > To: Forum for Physics Educators
> > > > Subject: Re: [Phys-l] FW: universal gravitation lab
> > > >
> > > > From: WC Maddox
> > > >
> > > > If anyone wants to do a real equipment experiment involving gravity,
> > > > Tel-Atomic has a version of the Cavendish experiment that uses a
> > > > computer to analyze the data. The apparatus cost ~ $2,000. In the
> > > > past this experiment often didn't get done due to the weakness of the
> > > > force and the sensitivity of the apparatus to vibration. If anyone
> > > > wanted to do it when I took advanced lab they had to come in at night.
> > > >
> > > > End Message
> > > >
> > > > _______________________________________________
> > > > Forum for Physics Educators
> > > > Phys-l@carnot.physics.buffalo.edu
> > > > https://carnot.physics.buffalo.edu/mailman/listinfo/phys-l
> > > >
> > > >        
> > > --
> > > "Trust me.  I have a lot of experience at this."
> > >              General Custer's unremembered message to his men,
> > >              just before leading them into the Little Big Horn Valley
> > >
> > >
> > >
> > > _______________________________________________
> > > Forum for Physics Educators
> > > Phys-l@carnot.physics.buffalo.edu
> > > https://carnot.physics.buffalo.edu/mailman/listinfo/phys-l
> > >
> > > !DSPAM:3440,45d135b4323448389278370!
> > >      
> > _______________________________________________
> > Forum for Physics Educators
> > Phys-l@carnot.physics.buffalo.edu
> > https://carnot.physics.buffalo.edu/mailman/listinfo/phys-l
> >
> >    
> _______________________________________________
> Forum for Physics Educators
> Phys-l@carnot.physics.buffalo.edu
> https://carnot.physics.buffalo.edu/mailman/listinfo/phys-l
>
>
>