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Unexplainable phenomena

  1. Jul 16, 2007 #1
    I found a site about this book on metaphysics or something, and the author tried to give some examples of where physics falls short or contradicts itself... this guy was clearly no scientist, but I couldn't think of a good explanation for a few things he pointed out, so maybe we can =)

    "As we all know, perpetual motion machines are impossible, and claims of such devices are a clear sign of bad science. Yet our science states that an object dropped into a tunnel cut through the Earth would be accelerated to the center by gravity, then decelerated as it approached the other end, only to be accelerated down again, over and over – endlessly. This describes an actively operating mechanism that never ends and never drains a power source – an impossible perpetual motion scenario, according to today’s physics."

    "How can freezing water expand, even bursting metal pipes, with no energy input to explain it? A balloon left in the sun will expand and burst, in the process doing work against the surrounding atmosphere and its elastic skin, which is balanced by the energy input from the sun, so it is no mystery. However, freezing water has no energy input -- in fact, just the opposite. Energy continually drains from the water as it cools toward freezing. So, how does the water suddenly expand with such force from within that it easily bursts metal pipes?"
  2. jcsd
  3. Jul 16, 2007 #2


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    Homework Helper

    I could describe a pendulum the same way. The point is there's no way to extract energy from it.

    The water is losing energy: some is radiated as heat, and some is used to do work on the container.
  4. Jul 16, 2007 #3
    hmmm, yeah I get the first one... but the second one... ummm... don't the H20 molecules have less KE in ice than in water since the ice is at a lower temp. than the water, shouldn't that mean that the molecules should exert less outward pressure and volume should decrease... but instead volume increases... where does the energy for this outward pressure (which is considerable enough to break pipes) come from? I think thats what hes asking
    Last edited: Jul 16, 2007
  5. Jul 16, 2007 #4


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    Yes, the first one is simply a misunderstanding of what a "perpetual motion machine" is and what the issues with it are. I believe kids first learn Newton's first law in junior high...

    For the second one, he's just plain wrong in his assertions. There is a change in energy in a freezing pipe, quite obviously. Your freezer doesn't freeze water if it isn't plugged in. Water expands when it freezes due to the crystal structure and when a pipe full of water freezes, the pressure increases, which then also changes the freezing point and energy of the water.

    This author is simply displaying his lower-than high school level understanding of science (though the specifics of what happens to water are a little complicated, the idea that it expands is known to high schoolers). Pathetic, really.
    Last edited: Jul 16, 2007
  6. Jul 16, 2007 #5
    as Russ put it, the author is really pathetic.... really.

    for the second one, from classical thermal dynamics:

    by expanding, the ice actually loses more internal energy, there is no contradiction at all. In the author's mindset, he should be more troubled by how other liquids shrink when freezing!
  7. Jul 16, 2007 #6
    Where does he suggest we cut this proposed tunnel? :rolleyes:
  8. Jul 16, 2007 #7
    duh, that explains a lot for his ridiculous comments!!:grumpy::grumpy:
    if u call a pendulum continuing endlessly with its amplitude constant(thats what that earth stuff is equivalent to) a perpetual machine, you really dont understand the meaning of perpetual machine!!
  9. Jul 16, 2007 #8
    that is called SHM by SCIENTISTS
  10. Jul 16, 2007 #9
    Last edited: Jul 16, 2007
  11. Jul 16, 2007 #10


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    Notice that the Curezone site is sponsored almost entirely by manufacturers of 'body cleansing' and 'colon newal' products; in other words, things that make you ****. The article iself had that effect on me. :grumpy:
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