Question

Are all sounds audible to us? What is the audible range of frequencies for human beings? What are other sounds called, which are beyond this range?

Answer 1

1. No, audible sounds are those which fall in the range of 20 Hz to 20,000 Hz frequency.
2. The sounds whose frequency is less than 20 Hz are called infrasonic sounds.
3. The sounds whose frequency is more than 20,000 Hz are known as ultrasounds.
4. Infrasonic and ultrasonic sounds are inaudible sounds for humans.
5. Ultrasound is used by doctors to get pictures of the body organs.
6. It helps doctors to diagnose the causes of pains, swelling and any infections in the internal organs of the body.