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Just a little thought

  1. Apr 22, 2010 #1
    Why is it that smoke signals can propagate information over longer distances than sound signals?
  2. jcsd
  3. Apr 22, 2010 #2
    As smoke rises, people will be able to see it from far due to light. However, for sound signals, the sound wave will be absorbed by objects and thus, the wave will dissipate over a distance.
  4. Apr 22, 2010 #3
    As elitewarr said, it's a matter of light versus sound.

    It just happens that sound attenuates faster in air than light. Replace the air with water, and you have the opposite.

    (You could also replace the air with steel for a clear victory for sound, or replace the air with a vacuum for a clear victory for light).
  5. Apr 22, 2010 #4
    Since you are talking over the internet, I assume you are asking humans this question. Generally we can see further than we can hear in our normal environment.

    But, ask a whale a similar question and he will laugh at you. He can hear and communicate across half the world by submerging to the depth of the SOFAR channel, which acts as an acoustic waveguide. Yet, he can not see past the horizon on a clear day, at the surface.

    By the way, whales have had their own global internet for many millennia.
  6. Apr 22, 2010 #5
    Aren't you a clever cookie
  7. Apr 22, 2010 #6


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    Cause a 1 km peak can be easily seen from 10 km, while a bang that can be heard at 10 km will blow you era drums. (Heavily depending on weather conditions)
  8. Apr 22, 2010 #7
    Smoke rises, and on a calm day very high. This can be seen from afar.
    If done properly and under the right atmospheric conditions, a sort of "Morse code" or native language smoke code, can be very effective for long distances.

    Drum beats or horn sounds are used as well, but for much shorter distances, and usually in the case of direct battle.
  9. Apr 22, 2010 #8
    First of all you have to look at where in the past sound and smoke signals were used and why. In a jungle with a canopy of trees, the smoke signals would be dispersed, mixed, and combined. In say the mountains, smoke would usually be blown, so horns were used. In flat plains where there was no tree canopy, and often still air conditions, smoke would be used.

    So it more depends on the landscape where they were used.
  10. May 4, 2010 #9
    haha someones looking for answers for universe and everything(uni class).... :p
  11. May 4, 2010 #10
    LOL @ So Far channel. I just had to look that up, hilarious name.
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