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Why does elecricity kill? What causes a magnet to be a magnet?

  1. Sep 2, 2009 #1

    PrincePhoenix

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    Just a couple of simple questions.
    1-Why does electricity kill?
    2-What causes a magnet to be a magnet and certain things magnetic?
     
  2. jcsd
  3. Sep 2, 2009 #2
    1. Electricity in itself does not kill. As a matter of fact, it does not even hurt. What is dangerous about electricity is the combination of many electrons travelling (amperage) at very high "energy" (voltage). Without this combination, there is no danger.

    2. The magnetic property of matter, from the elementary point of view, comes from the movement of electrons around the nucleus.

    Cheers
     
  4. Sep 2, 2009 #3

    PrincePhoenix

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    What does high amperage and voltage do to kill? Like does it do anything to the heart or brain etc. And what type of movement causes magnetism?
     
  5. Sep 2, 2009 #4
    High amps and voltage causes severe burn on the body. If it travels through vital part, it will burn them, leaving you very little chance.

    Before going any further, do you know what creates a magnetic field???
     
  6. Sep 2, 2009 #5

    PrincePhoenix

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    Sorry I don't know.
     
  7. Sep 2, 2009 #6
    Hi there,

    That's fine. But it might important to understand where magnetism comes from, before trying to understand magnetism in matter.

    Ok, let's start from the start. Electric charges create an electric field. This electric field can interact with another electric field to develop a force on the initial charge. I hope you are following me up to now.

    Now, for magnetism, take the same electric charge and throw it, or just put it in motion. The movement of the electric charge now develops an extra magnetic field. Ok, so knowing that electrons are moving around a nucleus, each electrons creates a small magnetic field. Having many electrons orbiting, the magnetic field from each can be either increase or destroy the magnetic field of the others.

    Right. Cheers
     
  8. Sep 2, 2009 #7

    PrincePhoenix

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    Thanks a lot. If I am not annoying you can you tell how the magnetic field of one electron in creases or decreases the other's? does the direction of its spin have any effect?
     
  9. Sep 2, 2009 #8
    Forget about the electron spin. Don't think of the electron in an quantum mechanics mannet. Stick to the classical theory.

    Take the helium atom as a simple example. To make it really simple, take Bohr's representation of the atom. The helium atom has two electrons orbiting the nucleus. One electron creates a magnetic field. No problem up to now. The second electron also creates a magnetic field. To see the total magnetic field of the atom, you must sum the field created by the two electrons. In this case, the sum can be additive or destructive.

    Cheers
     
  10. Sep 2, 2009 #9

    PrincePhoenix

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    Thanks for explaining in a simplified way.
     
  11. Sep 2, 2009 #10

    Andy Resnick

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    1) the saying is "it's the volts that jolt, but the mills that kill". That is, a high-voltage low-current shunt through the body will not kill you, but simply act on your skeletal musculature, while a low-voltage high amperage (mills = milliamps) shunt can induce cardiac arrythmias (and death) by interfering with the timing control.

    2) There are different kinds of magnets: ferromagnets/ferrimagnets, paramagnetics, and diamagnetics. The first two are 'permanent' magnets, in that they generate a magnetic field all by themselves. The other two describe how materials respond to an applied magnetic field; either by becoming oriented with (paramagnetism) or opposed to (diamagnetism) the applied magnetic field. If we are discussing the phenomena in terms of classical physics, the situation is analogous to the polarization of a dielectric.
     
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