The Physics
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Opus in profectus

Interfaces & Barriers

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Discussion

interface

absorption

Sound, for example…

The characteristic acoustic impedance (specific acoustic impedance?)…

Z = ρv

is important when calculating the amount of reflection and transmission at an interface. For the reflected portion, notice that when Z2 < Z1, the sign of the reflected portion is negative, which indicates a change of phase.

R =  Z2 − Z1
Z2 + Z1
T =  2Z2
Z2 + Z1
refelcted pressure amplitude transmitted pressure amplitude

obstacles and openings

Diffraction is the bending or spreading of light through an opening or around an obstacle.

Goethe "flexibility of light"

Why is it possible to hear around corners, but not see around them?