Polymers, whether natural or artificial, are big molecules made by linking up smaller repeating chemical units. The most common âbackbonesâ for polymers are chains of carbon or silicon, each of which can bond to four other atoms. Polymers, whether natural or artificial, are big molecules made by linking up smaller repeating chemical units.
Details About Pitch. Although for most practical purposes, the pitch of a sound can be said to be simply a measure of its frequency, there are circumstances in which a constant frequency sound can be perceived to be changing in pitch.
The decibel (dB) is used to measure sound level, but it is also widely used in electronics, signals and communication. The dB is a logarithmic way of dscribing a ratio. The ratio may be power, sound pressure, voltage or intensity or several other things.Later on we relate dB to the phon and the sone (related to loudness). But first, to get a taste for logarithmic expressions, let's look at some numbers.Note also the factor 10 in the definition, which puts the 'deci' in decibel). Sound pressure, sound level and dB. Sound is usually measured with microphones and they respond (approximately) proportionally to the sound pressure, p. Now the power in a sound wave, all else equal, goes as the square of the pressure.