Blow throughout the highest of a glass bottle, and also you’ll get a whistle-like sound. Put some liquid in there and the pitch of the sound adjustments. Our vocal tracts are principally the identical factor: a tube with a gap on the finish. However as Joe Hanson reveals on this Be Sensible video, our skill to vary the form and resonance of our vocal tract by transferring our tongues and lips permits us to make a variety of vowel sounds. Get pleasure from this dive into the world of linguistic physics! (Video and picture credit score: Be Sensible)