Question

distinguish b/w ultrasound and infra sound with examples

Answer 1

low frequency sounds which cannot be heard by us is known as infrasonics.

objects that vibrate at frequency of about 20,000 which also cannot be heard by us are known as ultrasonics

Answer 2

frequency of sound below 20hz is known as infrasound and frequency above 20khz is known as ultrasound.
these frequencies is not audible to human ears.
examples of infrasound: some animals like whales , elephants communicate using infrasound over long distances
examples of ultrasound: dog whistle and sound produced by a bat.
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