The jet engine. Explained well.

While prima facie, this may seem funny, if my late father (who taught 650+ pilots in his school over 13 years) were around, he'd have taken this man's hand and congratulated him on the excellent and succinct chapter on the basics of a turbojet engine.

When my father took us to see a circus, he'd point to the clown we all were laughing at as he dangled precariously on the trapeze, falling awkwardly, and with great comic timing on to the safety net below, and tell us that the person in that costume is actually the most accomplished trapeze artist in that tent, because to do what the clown did, which was making a joke out of stuff that would have killed a lesser performer, takes tremendous practice and confidence in one's skill.

Now, while I do not know if this professor intended to be funny or that is just his teaching style (I remember seeing another excellent video of his on the Indo-Nepal border), but whichever it is, he is good. I wish we had teachers like him when we were in school.