Question

what is infrasonic sounds

Answer 1

infrasonic sound are those sound which can't be hear by a normal human as its range is greater 20k hzts and lesser then 20 hzts

Answer 2

Infrasound, sometimes referred to as low-frequency sound, is sound that is lower in frequency than 20 Hz or cycles per second, the "normal" limit of human hearing. Hearing becomes gradually less sensitive as frequency decreases, so for humans to perceive infrasound, the sound pressure must be sufficiently high.