1. The problem statement, all variables and given/known data The two components of a double star are observed to move in circles of radii r1 and r2. What is the ratio of their masses? (Hint: Write down their accelerations in terms of the angular velocity of rotation, ω.) 2. Relevant equations Newton's 2nd law? law of gravitation? 3. The attempt at a solution I don't know what a double star is and hence I don't know what the system is doing.