Re: The Rise and Fall of Simple Machines.

[Ludwik Kowalski <KowalskiL@MAIL.MONTCLAIR.EDU>]

Dear Teacher:

For the second time you are asking me to deal with something
else that I wanted. My original question was "where am I
wrong?" in making a generalization from what we did in the
lab and what I read about Joule's work. It was my own
exercise in critical thinking and you say absolutely nothing
about it (after the implied rejection). Why is it so?

>>> .. energy (mechanical or thermal) can be said to be
>>>  "work done on a system" or "heat supplied to it".

You also totally ignored my comment on "accepting things on
faith". It was your idea, I responded and you totally ignored
the comment. It is very important to me that subsequent
messages address the issues raised in previous messages, and
that we keep the discussion on the level of what I am supposed
to know so far. We did not learn anything about physics of
engines yet and I have no idea what is Y in your unfamiliar
equations (see below).

                    Y A
                k= -----
                     L
                                       2
           1      2    1         / dL \
    PE  = --- k dL  = --- Y A L | ---- |
      e    2           2         \  L /

equating to dQ:

            = c m dT = c rho A L dT

                                 2
                     Y     / dL \
             dT = ------- | ---- |
                   c rho   \  L /

My observations were made on the basis of simple machines
and calorimetry. Why are you focusing on heated springs?
Why did you mention the spring in the first place? I know
nothing about heated springs and I am sorry I started to make
bad guesses. The only connection between heat and energy I
know about is that 4.18 J of work raises the temperature by
nearly the same amount as 1.00 calorie of heat. "Work is not
lost, it exists in the form of heat". That is just another way of
saying what was quoted above.

Sorry for bringing the initial sentence back again; I really
want to know what is wrong with it it. Can it be explained
in my language or should I just accept your criticism and
wait till I know more physics? Perhaps you are right,
students should not try to act as scientists; critical thinking
at my level should be strongly discouraged. Learn what
others found first and try to be creative later.

Respectfully, H.S.S