I thought this was a better visualization, though he doesn't seem to mention you have to consider the whole system of the cup and his arm https://youtu.be/JDJKf

I thought this was a better visualization, though he doesn't seem to mention you have to consider the whole system of the cup and his arm https://youtu.be/JDJKfs3HqRg https://youtu.be/JDJKfs3HqRg