Page 12 - SoundWaveModule
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When watching the beleq drum, have you ever paid attention to the tools like in the video above? the
sound produced will sound different when hit slowly and hard?
how does the sound of the musical instrument "gong" when struck
hard and slowly? write down your opinion.
a. Sound Intensity
Sound intensity is a power carried by sound waves (per unit area) in a direction perpendicular to the
direction of wave propagation. The formula for sound intensity itself can be written in the following
equation
From the equation above, you can also see that the sound intensity is inversely proportional to the
square of the distance. So, if we make a comparison between sound intensities from the same source
but heard from di erent distances, we can write this down with the equation:
It turns out that the loudness of the sound heard by the ear is not directly proportional to the
intensity of the sound. Because the range of sound intensity that can be heard by humans is very
large, a quantity is created that expresses the intensity in a smaller number. This quantity is called the
sound intensity level abbreviated TI.
b. Level of Intensity
What is meant by the sound intensity level is the logarithm of the ratio between the sound intensity
and the intensity of the hearing threshold.