Describe what happens. Do these observations support or refute the idea that gravity could be caused by the Earth's atmosphere? Lastly, consider the idea that it could be the rotation of the Earth that causes gravity. Consider the apparatus shown here. In this setup a freely hanging ball is suspended in such a way that it can be made to rotate around the central post in a circle. If rotation causes an inward pull on objects what should you observe when this hanging ball rotates? Would it swing inward or outward as it rotates, or would it remain hanging straight down