Answers Problem Set 2

1.   4x10⁷ Newtons
2.  Big player is moving backward at .01m/s.  Small player is moving backward too, at .02m/s
3.  50 solar masses implies its orbit is 1/sqrt(50) years = 4.4x10⁶ seconds.
4.  42km/s
5.  Because circular orbits in a disk never cross each other.  If orbits are coming in perpendicular to each other, then collisions are inevitable, forcing the orbits into a disk.