Greg:==
>I think another problem with Second Law problems is that there
>is a 'folk thermodynamics' which is very solidly ingrained in
>us. We drop glasses and they fall down and break. The pieces
>never come together and jump up. Thus 'folk gravitation' and
>'folk thermodynamics.' The real difficulty, and where science
>has had a lot of trouble convincing people, is that detailed
>examinations often show folk theories to be wrong. Look how
>long it took for people to learn that heavier things don't
>fall faster than light things because of gravity. And this
>is a relatively simple experiment!
This is great example! Not long ago I read a great little
book about the fab four (Copernicus, Kepler, Galileo and
Newton). The author claimed that if asked in a survey,
practically all laymen would claim that they believed in
Newtonian (as opposed to Aristotelean) physics. Yet if you
quizzed them on how they expect things to behave you'll
find most laymen are really Aristoteleans. Aristotle's
physics wasn't really so bad as people might think and
it definitely corresponded to basic intuition and common
sense.
Reading this authors claim reminded me of an argument I
had with a college roommate, an economics major. I told
him that if you drop balls of different weights they will
hit the ground at about the same time. He laughed. The
more I insisted the more he laughed. He thought I was
pulling his leg.
Here's a simple experiment one can do to prove that the
earth is not moving. For the proof to work one must
transport oneself back in time to the day when Aristotle's
physics reigned supreme and before Galileo's telescopic
observations (should have) put the issue beyond doubt.
Go to the top of a building and drop a heavy object. Observe
that the object falls parallel to the side of the building,
in a straight line. If the earth were moving the object
would obviously follow a curved path and if it were moving
as fast as those Copernicans said, it would fly off almost
parallel to the earths surface and out into space. To believe
otherwise would be to believe in occult forces which mysteriously
kept the object moving at the same speed as the earth as it
was in free fall.
Now I'd like to change the subject a little and go back to
the issue of the "simple experiment". I can remember several
times thinking why it took so long for someone to do such
a simple experiment. I was very surprised to find not long
ago that the experiment had been done several times, the
first written record being from a fellow named Philoponus in
the 6th century!! :
"If you let fall from the same height two weights,
of which one is many times as heavy as the other,
you will see that the ratio of the times required
for the motion does not depend on the ratio of the
weights, but that the difference in time is a very
small one" -- Philoponus
The question naturally arises: How did Aristotelian
physics manage to survive for several hundred more
years in the face of this empirical refutation?
[...]
Brian Harper
Associate Professor
Applied Mechanics
The Ohio State University
"It is not certain that all is uncertain,
to the glory of skepticism." -- Pascal