Or "nous" in French, or "noi" in Italian or "nós" in Portuguese. :)
Since a good chunk of Esperanto comes mostly from the Romance languages, I would not be surprised if this is no coincidence. Just like "vi" starts with the same letter as "vosotros" in Spanish, "vous" in French, "voi" in Italian, and "você" in Portuguese.
Here's my general link on sound in the course:
Inside that one is a link to this: