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Homework Help: Sound and Light word problem.

  1. Apr 25, 2012 #1
    1. The problem statement, all variables and given/known data

    Lighting strikes the ground 1.00 km form an observation point. Calculate the delay between seeing the flash and hearing the thunder. (Temperature @ 15⁰C)(Speed of light = 2.99 x10⁸ m/s)

    2. Relevant equations


    3. The attempt at a solution

    Speed of the sounds is = 340 m/s 1,000/340 = 2.94 sec

    Speed of the light is [tex]2.99 x 10^8 m/s[/tex] [tex](1,000) \div (2.99 x10^8) = 3.3 x 10^-5[/tex]

    2.94 - 0.000033 = 2.939967 seconds
  2. jcsd
  3. Apr 25, 2012 #2
    Sure, but basically it's silly to even consider the light time delay because the scale is so small that sound turbulence/reflections will perturb the sound much more than the 3*10^-5 light time delay.
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