Question

The sound of frequency less than 20 Hertz is known as
(a) Ultra sonic
(b) Infra sonic
(c) Sonic
(d) None of these

Answer 1

Answer:

The sound of frequency less than 20 Hertz is known as infrasonic sound.

Answer 2

The right answer to the asked question is Option B.

The sound of a frequency of less than 20 Hertz is known as Infra Sonic Sound.

An ideal frequency at which human beings can hear sound is between 20Hz to 20kHz. The frequencies of sound that are lower than 20Hz are considered as infrasonic sound. The frequencies of sound higher than 20kHz are regarded as ultrasonic sound.