Tag: audible, infra and ultra sound with its application

Answer is C.

The generally accepted standard range of audible frequencies is 20 Hz to 20,000 Hz, although the range of frequencies individuals hear is greatly influenced by environmental factors. 

A person who has hearing within the normal range can hear sounds that have frequencies between 20 Hz to 20,000  Hz. This frequency range is called audible frequency range. Since the frequency 30,000 Hz is above the audible frequency range human ear cannot audible it clearly.

Human ear can hear sound having frequency range from $20 \ Hz$ to $20 \ kHz$.

Human ear can hear sound having frequency range from  $20 \ Hz$ to $20$ $kHz$.

The audible range of frequency is $20\;Hz$ to $20,000\;Hz$

The frequency range of human hearing is about 20 Hz to 20 KHz. This range of frequency is known as audible range. Human cannot hear the sound with frequency above or below this audible range. Hence the sound with frequency 30,000 Hz cannot audible to human ear

The audible range of frequency is $20\;Hz$ to $20,000\;Hz$

The audible range of frequency is $20\;Hz$ to $20,000\;Hz$

The sound intensity of a human whisper has an intensity of approximately $30\,dB$.