Leyden note:
this is the coat hanger & string activity; clicking the metal and hearing the sound thru the air --- vs. --- the sound directly to the ear thru the string
With the second method described, the hanger will sound like Big Ben! Since the hanger
has a small surface area, it is not an efficient radiator of sound - the small surface area
cannot drive many air molecules
Leyden note:
remember there are no air molecules - just air particles -- a mixture of oxygen molecules and nitrogen molecules; etc.
into vibration. The string provides an effective
mechanism for propagating the vibrations of the hanger directly into your ears where
they are converted into audible sound. Thus, more energy is delivered to your ears per
unit time than when the energy travels through the air and, consequently, the sound is
louder.
p 222 --- Physics Begins With an M - Mysteries, Magic, and Myth