Ringworld is an artificial world constructed in the shape of a giant ring that rotates around a star similar to our sun. The radius of the ring is 1.53x10^11m (from the sun to the ring). The mass of ringworld is 2.1x10^27kg and its simulated gravitational acceleration is 9.73m/s^2. Determine how fast the inner surface of the ringworld is moving to experience a "gravitational" (no idea why this is put in quotations in the question) acceleration of 9.73 m/s^2.
Acentripetal=v^2/r or =4π^2(r)/T^2
Any combination of the above also work.
The Attempt at a Solution
How do you find the mass of the central body and the orbital period? It seems impossible to do anything without knowing one or the another. I don't know where to start.
Any help is appreciated. Thanks.