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Longitudinal waves in circuits?

  1. Nov 27, 2004 #1
    im just confusing about the electrical conduction in the electrical circuits
    I mean, for example,
    -an alternate voltage means that the electrons move back and forth in the circuit?
    -if really this happens, then the electric waves in the circuit are LONGITUDINAL, because by definition this waves moves in the same direction that the movement

    -but this led me to another question. How act a filter with longitudinal waves?
    For transversal waves is easy to see it like a slot that only let pass the waves that correspond to its size. But is less intuitive for Longitudinal waves, (if such filters exists)

    any help appreciated
    Last edited: Nov 27, 2004
  2. jcsd
  3. Nov 28, 2004 #2
    Is this a N.Tesla question?
  4. Feb 24, 2009 #3
    Filters work by blocking certain frequencies or bands of frequencies, not amplitude.
    Generally filters are used in electronics not wave mechanics, so for example you could have a sensors that converts an acoustic wave in a solid material(its like vibration) into an electronic signal and all waves above a certain frequency e.g 10Hz could be blocked. If the waves in the solid material were longitudinal or traverse would not matter when it is in electronic it can be filtered.
    hope that clears it up for you.

    Also i would not be confusing electric current/voltage with mechanical waves(ie waves in solids liguids or gasses). They are separate entities. In alternating current(AC) energy in the form of a current conducts in one direction for a set period of time, its amplitude climbing from zero to peak and back to zero, it then starts conducting in the opposite direction for the same period of time, again climbing from zero up to the peak and back to zero. So although mechanical waves look like AC electricity, its not the same thing, mechanical waves work at the molecular level while electricity works at the electron level. Not good to mix them.

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