Hello, I have a beginners question about physics. Let's say that you are sitting in one of those swivel chairs - one that can rotate back and forth (about the z-axis). And let's also say that you are sitting in the middle of the room, just out of reach of anything that you can grab on to. Your feet are on the chair, not touching the floor. Your goal is to turn around in this chair. My inborn sense of physics tells me that in order to accomplish that, I should hold my arms outward and to swing them in the direction opposite of which I want to turn toward. Question 1: What concept of physics explains the reason why this method works? (I studied first-year physics, so I should probably realize the concept if you name it). Question 2: I noticed that the further I try turn, the more difficult it gets. In fact, if I rotate 180 degrees and sit still for a while, and then try to turn another 180 degrees in the same direction, the chair will resist. It's almost as if the chair remembers my state of motion. As if the chair has a memory and a conscience... . Can anyone save my sanity before it's too late by explaining this phenomenon? Thank you in advance for the help.