So i was presented this question and I would not even like the answer but just the path to walk on. Can you help? In order to simulate the Earth gravity on a space habitat of 100m diameter, what spin rate of a donut-shape space habitat, in terms of RPM, should be. conversion of RPM is 2(pi)/60 radians/sec where do I even begin???? I have read that a station 2km in diameter would spin at 1 RPM to simulate a confortable earth-like gravity. Just in my head I came up with the answer of 20 RPMs for a station 100m in diameter, but I have to show my work and explain the theory behind it, but i'm just going on intuition. Is there hope for me? Oh yea, I have to hand this in, in three hours and it's the only question out of thirty that I don't even know where to start.