physics
posted by kim .
A projected space station consists of a circular tube that will rotate about its center (like a tubular bicycle tire) as shown in the figure . The circle formed by the tube has a diameter of about 1.1 km. What must be the rotation speed (revolutions per day) if an effect equal to gravity at the surface of the Earth (1.0 g) is to be felt?

acceleaertion=w^2 r
w=sqrt(9.8/550)=
then in rev/day,
w=(sqrt(9.8/550) )*3600(24)/2PI rev/day
I get something over 1800 rev/day