The sound waves having frequencies less than ________ Hz are called infrasonic waves.
Show answer & explanation
Correct answer: A
Explanation
The Correct answer is option 1 i.e. 20
- Sound waves with frequencies below the range of human hearing, which is typically considered to be less than 20 Hz, are referred to as infrasonic waves.
- These waves are not audible to the human ear but can be perceived by certain animals, such as elephants, whales, and some species of birds.