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What is sound?
Caused my mechanical vibrations and travels as a wave
Sounds in the range of 20-20000Hz can be detected by humans
Cannot travel through vacuum
Pitch increases as frequency increases
Loudness increases as amplitude increases
Waves can be reflected and retracted
What is ultrasound and how can it be used?
Electronic systems can produce ultrasound waves with frequencys higher than humans can
They can tell how far away boundaries are when they are reflected eg creating picture of
baby during pregnancy
Used in industry for cleaning and quality control