Here is a video from the Bell Laboratories archives. It describes the similarities in wave behavior in all mediums, be it electric, sound, or mechanical.
On an elementary conceptual level, this film reflects the multifaceted scientific hyperthinking that was typical of a Bell Labs approach. Host Dr. J.N. Shive’s presence as a lecturer is excellent – it’s understandable by a layperson even when he branches into equations, because he uses copious amounts of real-world examples to bolster the material.