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Homework Help: Bats and sound pulses

  1. Apr 16, 2009 #1
    1. The problem statement, all variables and given/known data
    A bat emits short pulses of high-frequency sound and detects the echoes.
    a) In what way would the echoes from large and small insects compare if they were the same distance from the bat?
    b) In what way would the echo from an insect flying toward the bat differ from that of an insect flying away from the bat?

    2. Relevant equations
    Written Response

    3. The attempt at a solution
    a) absolutely no clue. maybe more returning sound waves from a larger creature?
    b) possibly something about the doppler effect?
  2. jcsd
  3. Apr 16, 2009 #2
    Hi m.l.

    In regards to a), I think you're probably correct. It seems reasonable that the larger the object, the more intense the reflected sound wave.

    In regards to b), I think you're also correct. If the insect is moving away, the echo returned by the object would have a lower pitch due to doppler shift, and vice versa.
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