Question

A range of loudness of sound of 70-90 Hertz is rated as
A. Very loud
B. Uncomfortable
C. Painful
D. Quiet

Answer 1

Sound is a vibration that propagates as an acoustic wave through a transmission medium such as solid, gas, or liquid. Organisms perceive these sound waves through brain waves and the normal perception of sound frequency is between 20 Hz and 20 Hz which is the normal audio frequency range.

Complete answer: Inaudible sound- Human ears cannot detect frequencies below 20 Hertz and humans cannot detect the sound of more than 20000 Hertz also. So the frequency of sound below 2o hertz and above 20000 hertz comes under inaudible frequencies. The low frequencies which humans cannot hear are termed as infrasonic sound and the high frequencies which human ears cannot perceive are known as ultrasonic sound.
Some animals like dogs have the capacity to detect sound frequencies of more than 20000 hertz. The police department uses whistles with frequencies higher than 20 thousand hertz so that dogs alone can hear. These sound frequencies are helpful in many ways in the field of research and medicine.
Audible sound- We, humans can detect sound frequencies between 20 hertz to 20000 hertz. So the sound frequencies between 20 hertz to 20000 hertz are called an audible sound. The human ear is so sensitive to every minute pressure difference. It can detect the slightest change in pressure.
As we get older we are exposed to sound for a very long period of time and our ears get damaged and the audible frequencies decrease. The highest frequency a middle-aged person can hear is 12 to 14 kilohertz.

Hence the answer is option A, very loud.

Note: unwanted sound is the major contributor to air pollution in this modern era. These sound waves have a frequency value of 80 Hertz and above. Moderate conversation produces about 60 Hertz of sound frequency and loud conversation is about 70 Hertz, scooter produces about 80 Hertz, larger vehicles like trucks and buses will produce 90 Hertz, airplanes and jets produce 150 Hertz and rockets 180 Hertz. A noise level between 70 to 90 Hertz is very loud.