Question

The loudness of sound is determined by its _____________

• A. Amplitude
• B. Frequency
• C. Velocity
• D. Source

Answer 1

The correct option is A

Amplitude

Explanation for the correct option

In the case of option A, Amplitude

1. The loudness of sound is a phenomenon of sound depending on the amplitude of the sound wave. If the amplitude of the sound wave is large, then the sound is said to be loud.
2. The loudness of sound is directly proportional to the square of the amplitude of vibration, and it is expressed in decibel (dB). Therefore, sounds above 80 dB become noise to human ears.

Therefore, the loudness of sound is determined by its amplitude.

Option A is correct

Explanation for the incorrect options

In the case of option B, Frequency

1. You might suspect, that the higher the frequency, the louder we perceive a noise, but frequency does not tell us how loud a sound is. Frequency affects the pitch of the sound.
2. Intensity or loudness is the amount of energy of vibration and is measured in decibels (dB).

Therefore, option B is incorrect

In the case of option C, Velocity

1. There is no direct or inverse relationship between loudness and velocity

Therefore, option C is incorrect

In the case of option D, Source

1. Loudness depends upon the distance from the source, not the source.

Therefore, option D is incorrect

Hence, option A is correct.