Question

Loudness of sound is linked with _________.
A.) Amplitude
B.) Frequency
C.) Velocity
D.) Time period

Answer 1

Hint: Loudness of the sound is a subjective property. It depends on the sensitivity of the human ear and varies from person to person.

Complete step by step answer:

Basically, we feel that louder sounds are produced by larger vibrations of the source. If the loudspeaker cone moves backwards and forwards over a greater distance, a bigger disturbance is produced in the air and a louder sound result.
The loudness of a sound is a subjective property i.e., it depends on the human ear. The same sound is judged to be of different loudness by two people. A more objective measurement of loudness is the amplitude of the vibration.
The human ear is sensitive to sounds over a huge range of loudness. For example, the loudest sound that the ear can safely detect without suffering any physical damage is more that, one billion times more intense than the threshold of hearing (where sounds can just be heard).
The ear responds to sounds of different loudness in such a way that huge increases in amplitude are registered as small increases in loudness.
Loudness of sound is linked with amplitude. Hence, the correct option is A, i.e., Amplitude.

Additional Information:

Let us take a situation that, when your friend whispers to you in a voice so soft that he/she has to lean very close so you can hear what he/she is saying. Later that day, your friend shouts to you from across the gymnasium. Now her voice is loud enough for you to hear her clearly even though he/she is several meters away. So, it is clear that sounds can vary in loudness.
Loudness refers to how loud or soft a sound seems to a listener. The loudness of sound is determined, in turn, by the intensity of the sound waves. Intensity is a measure of the amount of energy in sound waves. The unit of intensity is the decibel (dB).

Note: Here students should understand the difference between the characteristics of sound so that they can answer this type of question easily. Students need to understand the fact that loudness and intensity are not always the same. Loudness is a measure of the response of the ear to the sound whereas intensity of the sound is the amount of the sound energy passing each second through the unit area.