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.
Amplitude measurement â¢ Sound pressure is measured in decibels (dB) on a log 10 scale relative to a reference level â¢ dB = 20 log 10 P 1 /P r where P r is a reference pressure level, usually the threshold of human hearing at 4 kHz.