Mon Prof Augmenté
Bat Echoes at Night
A bat flies through a moonlit woodland and sends out calls. The returning echoes come back at different times and with different shapes.
This picture is part of the full library
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Age 13: open this week
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In the picture
- The bat’s mouth: the outgoing call
- The tight arc from the moth: a quick echo from a small nearby object
- The narrow arc from the branch: a later echo from a farther object
- The wide arc from the tree trunk: a strong echo from a large object
Examples
- A shout in a canyon returns as an echo after a short delay.
- A parking sensor uses sound pulses to tell how close an obstacle is.
Key takeaways
- A longer echo delay means the object is farther away.
- Echo shape helps show an object’s size and form.
Carry on in the app
Three questions on this lesson. It has left the free week, so its quiz is for subscribers.
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