Re: cheap clean electricity (again) machines

From: Don Kelly (dhky_at_peeshaw.ca)
Date: 03/19/05 

Date: Sat, 19 Mar 2005 04:51:33 GMT

"Ed Earl Ross" <edearl@satx.rr.com> wrote in message
news:X1h_d.10048$8D.3643@tornado.texas.rr.com...
> Don Kelly wrote:
> > "Ed Earl Ross" <edearl@satx.rr.com> wrote in message
> > news:xa0_d.7278$8D.6686@tornado.texas.rr.com...
> >
> >>Stephen Sprunk wrote:
> >>
> >>>"Ed Earl Ross" <edearl@satx.rr.com> wrote in message
> >>>news:EvWZd.5889$Ux.3699@tornado.texas.rr.com...
>
> >>>>The simplest machines are the lever, wheel, and inclined plane,
> >>>>which make work easier, but do no work themselves.
>
> >>I believe my high-school physics teacher said that all machines are
> >>variations and combinations of the three simple machines. A screw
> >>is an inclined plane twisted around an axle. Gears are wheel and
> >>axle combinations. Rocker arms in an engine are levers. Etc.
> >>
> >>No lever, wheel, or inclined plane (nor any combination thereof)
> >>can produce power. They can change the form of power, as a lever
> >>converts large-movement low-pressure power into small-movement
> >>high-pressure power. They can also transfer power from one place to
> >>another, as an axle can transfer power from one end to the other.
> >>However, they do not produce power.
> >>
> >>Over-unity machines (alias perpetual motion machines) are impossible.
> >
> > -----------
> > Your conclusion is right but your teacher should have qualified his
> > statement to strictly mechanical machines. Electric motors and
generators
> > may also be considered as "machines" as is your computer (remember
Turing's
> > machine). "Machine" is a fairly broad term These things convert energy
from
> > one form to another but also are bound by conservation of energy.
>
> I believe my physics teacher was referring to mechanical machines,
> as the first definition in dictionary.com, given below.
> <quote>
> 1. A device consisting of fixed and moving parts that modifies
> mechanical energy and transmits it in a more useful form.
> 2. A simple device, such as a lever, a pulley, or an inclined
> plane, that alters the magnitude or direction, or both, of an
> applied force; a simple machine.
> </quote>
>
> The plethora of definitions make the term ambiguous, none of which
> are labeled specific to physics. For example, "machine" in the
> phrase /political machine/ is an analogy, but IMO a political
> machine is not really a machine.
>
> An electric motor contains a wheel-and-axle simple machine, which
> means an electric motor is (partly) a machine. Of course, a motor
> also contains other components, including at least one
> electromagnet, and may contain other components such as brushes or
> permanent magnets.
>
> The Quagmire
>
> <IMO>
> A permanent magnet is not a machine. The wire and iron in an
> electromagnet are not a machines; neither is an electromagnet,
> except when taking the form of a machine, such as a lever.
>
> When a magnet moves a piece of iron to itself, the combination and
> process do not comprise a machine.
>
> When an electromagnet moves a piece of iron to itself, the
> combination and process do not comprise a machine.
> </IMO>
>
> When an electromagnet moves the armature of an electric motor, it
> moves the wheel-and-axle machine. The action of moving the armature
> is similar to a magnet moving a piece of iron--is this process also
> a machine? I do not know. The process converts electric power into
> mechanical power and heat.
>
> An electric motor may be a made of a machine and a converter, or it
> may be made of two machines. I really don't care, electric motors
> contain at least one machine and act like machines; thus, they are
> machines.
> --
> Humbly--Ed
>
> Mark Twain
> "There is something fascinating about science.
> One gets such wholesale returns of conjecture
> out of such a trifling investment of fact."

-----------

My dictionary says "1) an apparatus using or applying mechanical power,
having several parts, each with a definite function, which together perform
certain kinds of work. 2)a particular kind of machine, e.g. a vehicle, piece
of electrical or electronic apparatus,etc. 3)...."
This is a bit broader than your strictly mechanical definition.
 However, in general, such things as transformers are not called machines
while motors with a mechanical component are.- as you say- called machines.
A solenoid can also be called a machine although there may be no lever,
wheel or inclined plane involved. It will do mechanical work.
All I intended was that "machine" has become somewhat looser than it was 200
years ago. 

-- 
Don Kelly
dhky@peeshaw.ca
remove the urine to answer

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