Date: Wed Dec 19 17:30:18 2007

Author: Machele Kindle

Subject: Re: two questions

I would imagine that the larva is pretty compact inside the bean, so the
bean can be seen to be a whole system. Thus, it's like us and we can
jump just fine using our muscles.


Anthony Lapinski wrote:
> A few of my science colleagues were discussing some physics/chemistry
> concepts.
> 1. Does anyone know how a Mexican jumping bean works? I believe there is
> an insect larva inside that can jump. How, then, does the bean rise upward
> since the forces are internal (and thus momentum is conserved)?
> 2) Water is a polar molecule, and a charged balloon will easily bend a
> stream of water. Hexane is not a polar molecule, and chemistry demo books
> say the stream should NOT bend. But if you put hexane in a buret, a
> charged balloon DOES bend the stream. A charged balloon should attract any
> neutral object, right? Something seems wrong here...
> Can anyone assist me with these questions?

For in the end, we will conserve only what we love.
We will love only what we understand.
We will understand only what we are taught. - Baba Dioum
Machele Kindle
Graduate Student
Ira A. Fulton School of Engineering
Arizona State University
(336) 408-8382