frame of references
Let me start with the video. Here is a guy flying a plane in a barrel roll and pouring some tea at the same time. Talk about multitasking.
How can he pour upside down? Well, there are two ways to look at this. First, I can look at this in the frame of the plane. For this case, I can invoke the fake force - centrifugal force. Oh yes, I am going to do it. You probably remember all your physics instructors warning you to never ever do this. Well, they say that because they are afraid you will do something bad with it. Here, I will only use the centrifugal force for good.
What is the…