Re: Over charged by my post office

In news:1142633275.714217.19400@xxxxxxxxxxxxxxxxxxxxxxxxxxxx,
dnsey <dnsey@xxxxxxx> typed:
Amanda Angelika wrote:

Apparently using Microwave magnetrons instead of spark plugs in your
engine one could use water instead of petrol, because a small
quantity of water will expand 1000 times it's volume in the liquid
to gas transition and Microwaves could actually make steam power the
power of the future :)
Only an exothermic reaction can be used to power a device.
Unfortunately the creation of steam (by any means) isn't one! The
actual reaction in a steam engine is, of course, the burning of coal,
etc., which in thias idea is simply relegated to the power station.

Well you do have a different process going on with microwaves. From what I
can gather from the basic Science sites (not that basic science is
necessarily always spot on) is a microwave oven uses alternating microwaves
which switches the molecules from pole to pole very quickly, which creates
friction on a molecular level and this creates the heat. Which explains why
microwaves don't do much to air or gasses because the molecules are to far
apart.

But what it does mean is microwaves would be very effective at heating water
beyond boiling point, (superheating) in a pressurised chamber, because
obviously in that situation the heat itself would increase pressure build up
between the molecules and this would in effect improve the effect of the
microwaves and create even more heat accelerating the process until the
pressure is released and the cycle starts again (which of course would also
advantage from residual heat left from the previous cycle).

But of course whether of not using microwaves to create molecular friction
in water and causing it to heat up in that way would in effect make it
similar to an exothermic reaction and make it useable as a fuel is another
matter.

However it is difficult (for a lay person at least) to draw direct
correlations between microwave heating and conventional heating processes
since in the case of microwaves the heat is a result of a molecular reaction
in the water itself, rather than simply the application of an external heat
source and of course one also has the aspect that pressurising the water
does serve to accelerate the process. which of course reduces the amount of
energy input one would require.

But of course whether this reaction would create net energy increase is
another matter, common sense and natural scepticism say probably not :)

However it may have some applications I think I read somewhere that
scientists have studied the feasibility of using water as a rocket fuel in
space because obviously in space one has very low pressure well it's
practically a vacuum so releasing hot pressurised liquids is more effective.
I suppose they could even provide pee powered retro rockets to aid Moon
walking LOL
--
Amanda


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