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Homework Help: Pebble falling into well

  1. Jan 16, 2005 #1
    A pebble is dropped into a well. It takes 15 seconds for the sound of the splash to be heard. If the speed of sound is 343 m/s how deep is the well?

    Please Help!!
     
  2. jcsd
  3. Jan 16, 2005 #2

    Curious3141

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    There was another recent problem in a similiar vein. Can you try searching for it ?

    This problem involves solving a quadratic equation. Do you know how to do those ?
     
  4. Jan 16, 2005 #3

    dextercioby

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    Since it's posted in the College section,it would be a shame if he didn't... :tongue2:


    Daniel.

    PS.Post your work.
     
  5. Jan 16, 2005 #4

    Curious3141

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    True. It seems strange that there's such a high degree of overlap between the standard of problems posed in the other forum and this one.
     
  6. Jan 16, 2005 #5
    Hey guys I posted this hoping for some help not attitude towards my question, isn't that what this forum is for???
     
  7. Jan 16, 2005 #6

    brewnog

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  8. Jan 16, 2005 #7

    dextercioby

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    This forum is indeed to help.Did u read the "sticky" on top of the list of threads??

    Post your work...

    Daniel.

    PS.We won't do the problems for you...
     
  9. Jan 17, 2005 #8
    help

    hint: 15 seconds is the time it takes for the pebble to fall + the time it takes for the sound to travel back up the well. Since t is a known in the equation, and the pebble falls the same height the splashing sound travels, the solution is obtainable through a quadratic function of x. You know t=15, a=g=9.8, v=343...
     
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