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Homework Help: Speed of sound/Dectecting insects

  1. Aug 3, 2006 #1
    I've looked throughout my book for the formula, and I've looked online to see if there were similar problems so I could figure out how to do this, but I can't find anything.

    A bat can detect small objects, such as insects, whose size is approx. equal to one wavelength of the sound the bat makes. If bats emit a chirp at a freq. of 59 kHz, and if the speed of sound in air is 340m/s, what is the smallest insect (mm) a bat can detect?

    Maybe it's easier than I think. I'm definitely not a physics person. I'm not asking for the answer, just some help in find the right equation :)

    Thanks for any help.
  2. jcsd
  3. Aug 3, 2006 #2
  4. Aug 3, 2006 #3
    Well. That's simple. I think the whole time I just wasn't reading "approximately equal to one wavelength.."

    So, 340 m/s * 1,000 = 340,000 mm/s / 59 kHz = 5,762.

    I've got to be doing something wrong/missing a step.
  5. Aug 3, 2006 #4
    Check the units.
  6. Aug 3, 2006 #5
    Duh. Yes. Thank you!

    5.763 :)

    I feel stupid. Now that seems like a REALLY simple problem.
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