I’ve only recently discovered Minute Physics, a production of Embry-Riddle Aeronautical University. They state, quite correctly in my mind, that if you can’t explain it in a minute, you don’t understand it. This echoes a statement by Bob Doms, of the University of Pennsylvania, who once said to our class, “You need to always be able to explain your work in one sentence so your mother can understand.”

This is close enough, from Minute Physics, ‘Why is the Solar System Flat?”: