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Calls of the Wild
  Teaching Guide

Activity 1: Grades 5-8
Bats and Echolocation



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  1. Why is there a delay in hearing the sound of the clap and its associated echo?
    (The clap travels a short distance to your ear. The echo's travel is much longer, from your hand to the wall and back to your ear)
  2. Suppose the speed of sound was 688 m/s. How would this affect your observations?
    (You'd have twice as many claps and returns in the same one-second period. The calculated distance to the wall, however, would still be the same.)
  3. Why was it important to maintain a steady beat?
    (To determine the time for a round trip, you needed to overlap the sound of a clap with the echo from the previous clap. This required a steady beat from which an average time could be taken.)



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