Andy,
Much of what you say is correct, but the release of pressure when the
bullet enters the first side of the can causes the CO2 to come out of
solution rapidly, adding to the displacement effect and increasing
the rate at which fluid is expelled (Just pop the top on a warm can
of soda and you'll see what I mean!). There's also a heating effect,
which may be minor. Try the same test with a container of cold water
or hot soda and you should see significant differences. If you
repeated the experiment with a can of hot soda, as I suggested in an
earlier email, I think you would see the effect significantly
enhanced. With cold water, nothing much would happen. Shake the soda
can first and you'll see a further enhancement, as you will increase
the number of nucleation sites around which the bubbles form. I
suspect that the soda was at room temperature in your photo.
Nineteenth century physicists studied such phenomena, but in the
twentieth century and now, they mostly have drifted toward molecular
phenomena and left studies of these issues to mechanical and chemical
engineers.
This is a significant issue with potential failures of power plants
(particularly nuclear ones, a great concern at Three MIle Island), if
a break occurs in a superheated water line (temperatures greatly
above the boiling point at atmospheric pressure occur routinely in
such systems) and was extensively studied in the 50s to the 90s and
is probably continuing today. When the pressure is suddenly released
from a pipe or vessel containing superheated water, boiling occurs
and the pressure can increase significantly which can lead to
destructive forces in the containing pipe or vessel. The phenomena
involved in the soda can experiment and the fracture of a pipe
containing superheated water are similar but result from different
physical effects.
I was peripherally involved in such studies years ago, but haven't
kept up with it.
Roger
On 4 Dec 2007, at 9:23 PM, ADavidhazy wrote:
Marilyn,
I am no physicist but I believe that once the bullet has entered the
can and it is pushing its way to the other side it displaces liquid
and this has to go somewhere and the only free space is the hole it
placed where it entered ... so backwards. Later on the second, exit,
hole appears and liquid is also able to go that way plus the bullet
drags some along as well probably.
In some way morbid this is related to the discussions about president
Kennedy's assassination.
Andy
Marilyn Dalrymple wrote:
Why is it the can blows out all the way around? I would think
that the side where the bullet goes in would sink in, the side
where the bullet leaves the can would go out. Is it due to the
"explosion" of the carbonated liquid in the can, or does the
bullet itself cause this?
Marilyn
