Physics
Frequency Spectrum Analysis in Signal Processing
Quick fact
A single second of CD-quality audio contains 44,100 amplitude measurements; frequency spectrum analysis can compress that into a handful of key frequency peaks, revealing the underlying musical notes.
Why this is interesting
You hear a single chord on a piano, but your ear somehow perceives multiple notes blending together—how does the brain (or a machine) disentangle that mixture? Frequency spectrum analysis provides the tool to unravel complex signals into their pure ingredients.