Re: breaking glasses

["William J. Larson" <bill_larson@CSI.COM>]

I have observed this effect often.  No, it is not because I'm a
clumsy oaf, thank you , it is entirely because of my recognition
of the importance of the reproducibility of any experiment.  ;-)

I too wondered. I decided that maybe it's because the glass
does crack, but not shatter on the first bounce. On the next
bounce there is a torque on the new cracks & it shatters.

==>I dropped a plate the other day and watched it bounce,
==>then break on its second impact. I think I've noticed
==>this happen fairly often, although my memory is
==>admittedly colored by selective attention and limited
==>to a fairly small sample. I talked to two friends in
==>the restaurant business who get to watch glasses break
==>all the time. They reported that it is very common
==>for glasses to break on second impact. One actually
==>offered this information without my asking, in a
==>fortuitous coincidence. My question is, why?

Cheers,
Bill Larson
Geneva, Switzerland
----- Original Message -----
From: Zach Wolff <zachary_wolff@YAHOO.COM>
To: <PHYS-L@lists.nau.edu>
Sent: 2000 March 25 9:00 PM
Subject: breaking glasses


> I dropped a plate the other day and watched it bounce,
> then break on its second impact.  I think I've noticed
> this happen fairly often, although my memory is
> admittedly colored by selective attention and limited
> to a fairly small sample.  I talked to two friends in
> the restaurant business who get to watch glasses break
> all the time.  They reported that it is very common
> for glasses to break on second impact.  One actually
> offered this information without my asking, in a
> fortuitous coincidence.  My question is, why?
>
> Zach
>
> __________________________________________________
> Do You Yahoo!?
> Talk to your friends online with Yahoo! Messenger.
> http://im.yahoo.com