Echoes of bats and men Echoes of bats and men echoesofbatsmen00grif Year: 1959 AIRBORNE ECHOES scope screen with a camera in which the fihn moves at a constant rate. While the spot moves up and down as the sound waves strike the microphone, the motion of the fihn draws a graph of sound pressure on the vertical axis against time on the horizontal axis. The resulting graphic picture of sound waves makes it easy to see the echoes which continue to arrive at the microphone a

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Photo credit: © Bookworm / Alamy / Afripics
License: Licensed
Model Released: No

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