PHYS1171 Lecture Notes - Lecture 8: Greengrocer, Sound Intensity, Sound
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The sound intensity, i, is compared to a reference value, io, of. 10-12w/m2 which is the faintest sound- aka the threshold of hearing ) If the intensity of a sound waves doubles, the intensity level : Increases by 3 db: the northern greengrocer, an australian cicada, can produce sound intensity levels of. What is the intensity of this sound in w/m2. Pressure: the atoms or molecules of a fluid have thermal energy (unless at absolute zero, hence, they move around and collide with each other. In each collision, there is a force applied and the atom/molecule changes direction. Consider a vertical column of fluid with a density , a height h and a cross- sectional area of a. the volume of the cylinder is ah. We can calculate the mass of the fluid using density: m = v = ah. The force at the bottom of the column is the weight of the fluid in the column:
