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2 questions

  1. May 11, 2005 #1
    yes well i think i will get right to the point on this one, my first question is this

    i heard about these group of people that live neer the Hoover dam, specifically, neer the output power lines, that are complaining about electromagetic radiation from the powerlines, magnatisim. now my first question is could this magnetic feild actually do any damage to these people?

    my second question came across when i was dusicussing with my JAVA teacher, might there be some kind of wire, coil, or system where that magnatisim is harnessed into energy to possibly be pumped back either into the power station or into more homes, if there is not specifically a simple wire/coil that could do this, might some cube like magnets attached to agenerator do this ( so that they spin in repulsion to the magnetic feild) either way this could either give more power to more people, eventually suplying the entirety of the world with one power station by using the natural magnetic feilds in a kind of web across the globe putting out electricity, harnesing the magnetisim used to travel that electicity, thereby creating more electricity to be pumped out to the rest of the world. or it might creatre a Perpetual Motion Mechine, this is not a wild theory or anything, im just curios.


  2. jcsd
  3. May 11, 2005 #2


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    No. The myth that power lines are harmful is essentially a hoax started by one particular reporter in the '70s. He made a career out of it (and fearmongering about microwave ovens).
    You mean stealing power via induction? Yes, its possible, but I would advise against it...
    Oh.....no. Induction is like resistance - its a form of load. Its how a transformer works. Any power you pull from those power lines by tapping the field around those lines is power lost to the power company. Steal enough and they notice the difference.
  4. May 12, 2005 #3
    I have to disagree with you there, in regards to the safety of high voltage power lines. I agree that microwaves are harmless when used to cook your food however.

    Here is my reasoning. High voltage wires such as those have an enormous electric fields around them. They can cause light bulbs to light up when held just a few meters below the wires. They also emit certain forms of electromagnetic radiation, including radio waves and low energy microwaves. It's kind of like cell phones; all of that light pounding your brain could cause tumors, but doctors aren't quite sure yet... I can say one thing from personal experience however. I used to keep over 100 bee hives, and let me tell you, when I brought my bee hives to pollinate crops located underneath the high voltage lines, they were always EXTREMELY mad when I had to mess with them (going through the hive, general work on maintaining them). I know the difference between irritated bees and angry bees, and these bees were generally extremely mad and aggressive. I know the power lines somehow affected them, so who knows if they have the same affect on us?
  5. May 12, 2005 #4


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    I think he was asking if the power company mightn't increase the efficiency of the grid and reduce the local health risk by trapping the energy being wasted by these fields around the power lines. This energy is just being radiated out into the air, isn't it?

    However, I'm sure that if the amount of energy that could be reclaimed by such a process were worth more than the cost of the process itself, they'd already be doing it.
  6. May 12, 2005 #5


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    There are two ways to link tumors to power lines: one is by statistical corellation (which is what the reporter did) and the other is by understanding how tumors form. How tumors form is understood extremely well and that understanding includes no possible mechanism for how a 60hz em field could cause a tumor.
    What doctors are sure of is that after enormous effort, no link has yet been established. The corrollary (as you put it) is a catch-22 that most people don't realize is meaningles: it is impossible to ever rule out a link - it is only possible to say no link has been found. And believe me - people are looking hard for that link. Its worth a lot of money to a lot of lawyers if they can find one.
    I don't get irritated by standing under power lines... I'm sorry, but that personal experience really doesn't tell us anything of value.
    There is energy lost to the air, and its lost in pretty much the same way as energy is pulled from an inductor (the field is so strong it induces currents in the air). The only way to get rid of that is to remove the air (there is also loss through resistance in the wire). But that really isn't the issue here: This may sound weird, but that field around the wires isn't lost (or radiated) energy, it is the very energy that the wires are carrying!
    Last edited: May 12, 2005
  7. May 12, 2005 #6


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    The WHO has ongoing studies on EMF's created by power transmission as well as smaller electrical lines in household settings. They have reported that there is absolutely no indications that there is any adverse effects on humans. Bees may be something different.
    Last edited: May 12, 2005
  8. May 12, 2005 #7


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    Perhaps a little more explanation is in order:

    What this particular reporter did is find a statistical correlation between living near large power lines and cancer rates. Yes, that's right: the correllation does exist (though it is very, very weak). The problem is that people tend to see correllation and assume causation and in a broad-based study like this, there are many, many coincident variables that could account for the correllation. In this particular case, the most likely culprit is poverty. Power lines are run more through low-income areas than high income areas. So assuming correllation equals causation, you could say poverty causes cancer (likely that there is a real relation), poverty causes power lines, power lines cause poverty, or even - economy cars cause cancer.

    If there really was a direct link between power lines and cancer, it would be possible to isolate it by, for example, exposing rats to strong em fields for a long period of time and observing cancer rates. Yes, such studies have been done and no, no increase in cancer rates have been found.
    Last edited: May 12, 2005
  9. May 12, 2005 #8


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    I would recommend a look at this site. I am still plowing through it, but it is well researched and refereenced.


    Here's a snipet from the Long Island Power Authority (LIPA). Granted, it is from a power company, but it's info is supported by other sources:

    Last edited: May 12, 2005
  10. May 13, 2005 #9


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    What about aiming a magnetron at something alive? Would that hurt it other than burns?
  11. May 13, 2005 #10


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    One unofficial rating of military radar systems is to specify the distance at which they can kill a pigeon. So yes a directed beam of microwave energy can do significant damage to a living organism.

    While only a single generation of human beings have lived in the electromagnetic bath in which we currently exist, hundreds of generations of smaller animals have survived without harm it that same bath, so it really does not seem that there is any significant danger involved.

    Any damage to high field strength EM radiation will be acute, not systemic. That means you will have a burn, not hidden DNA damage.
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