What does science of sound have to do with a door creaking?
When a door is moved, if there is any "sticking"' in the hinge
mechanism (or contact at the jamb), there may be a continuous
"stick-and-release" action. This may result in mechanical vibration
which will produce sound. Sound is the mechanical energy released
through the air (and through the door, too) based on some kind of
harmonic motion in the door's component parts, and stimulated by
moving the door. Science explains what the sound is and how it was
generated in this instance. Should we have a meter, science could
allow us to measure the sound.