Question

Sound of frequency above 20,000Hz is known as ​

Answer 1

Answer:

Sound of frequency above 20,000Hz is known as decibel.

Answer 2

Answer:

------ultra sonic-----

Ultrasound is sound waves with frequencies higher than the upper audible limit of human hearing. Ultrasound is not different from "normal" sound in its physical properties, except that humans cannot hear it. This limit varies from person to person and is approximately 20 kilohertz in healthy young adults.

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