A discussion with some friends: Suppose you have a large wheel, say 10 meters in diameter and a bell jar with a good vacuum inside, the wheel is rotating horizontally to Earth. In the jar is a bob, and it is on a 10 meter string which is connected to the center of the bell jar furthest from center. The bob is magnetic and held loosely by another magnet fixed to the wheel so there is just enough magnetic force to keep the bob pointed to the center of the wheel, So with the wheel spinning, I say the bob would have a bias, a force trying to move it off dead center of the bell jar. My buddies say no, there would be no force on the bob and there would be no motion away from dead center of the bell jar. Of course the whole affair is balanced by masses on the other side of the bell jar so the system doesn't wobble. So who is right? Me, saying the bob would not want to be dead center because there would be a force pulling it in the opposite direction of motion, or my buddies who say the bob would stay dead center with no bias forces trying to disrupt the pull of the magnet holding the bob inplace in midair center of the bell jar?