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Point source P2 Pi < Consider an idealized model with a bird (treated as the point (sound) source) emitting constant sound power, with intensity inversely proportional to the square of the distance from the bird. By how many decibels does the sound intensity level drop when you move from 0.99m to 3.21m away from the bird?
You blow across the open mouth of an empty test tube and produce the fundamental standing wave of the air column inside the test tube. The speed of the sound in air is 348.7m/s and the test tube acts as a stopped pipe. If the length of the air column in the test tube is 29.59cm, what is the frequency (in Hz) of the fundamental standing wave in the air column if the test tube is half filled with water? <