Web videos that involve physics are fun to watch. They can be even more engaging with the addition of a few well-crafted questions. VERITASIUM: THESE ILLUSIONS FOOL ALMOST EVERYONE (25 minutes · 32 questions · 3 pages) Audio illusions show us that hearing is about more than just sensing frequency. Which ones trick you every time? The video includes discussion of fundamentals, overtones, harmonics, timbre, the missing fundamental, Shepard tones, mondegreens, phantom word illusion, topophone, sou