Some taxes are inadvertently hidden, but others are consciously designed that way to disguise the cost of government. Itâs easy to see why: the total U.S. tax burden is equal to 56 percent of annual personal consumption spending.
Thus, the volume is proportional to the amplitude of the sound wave. The frequency of a sound wave is perceived as pitch. Humans can detect pitches within the acoustic range of 20 to 20,000 Hz, but we can't detect ultrasound or infrasound.
What determines the pitch of a sound wave? Pitch is determined by the frequency of the wave; intensity (loudness) is determined by the wave's amplitude. The vibrating source moves in some kind of periodic way, and thisâ¦ periodic motion will have some given period.