Saturday Learning Series - The Feynman Lectures (Part 1)

If you watch the Big Bang Theory, you may recall they reference Richard Feynman a few times.  For example, here.

They also mention his lectures.  Richard Feynman was a theoretical physicist and he gave some lectures on physics that were simultaneously understandable while being not too general in nature to be uninformative.  This is one of part of those lectures in which Feynman focuses on the Law of Gravitation.