Page 78 - Science Course 3 (Book 2)
P. 78
Mo10-L4b: How Do you Hear Sounds?
Ultrasound scanners convert high-frequency sound waves to images of internal body parts.
The scanner analyzes the ref ected waves and produces images, called sonograms, of the body structures.
SUMMARY
How Do you Hear Sounds?
The pitch is how high or low the frequency of a sound wave is. You create different pitches using
your vocal cords.
An echo is a ref ected sound wave. Ships use sonar to f nd underwater objects.
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