Eclipsing binary, mass.?

Question

An eclipsing binary is observed to have a period of 0.10 years and each component has a speed in its orbit of 19AU ( about 90km/sec) Assuming that both stars have the same mass and that their orbits are circular, calculate the separation of the two stars in AU and the mass of each star relative to the mass of the Sun.

Answer 1

If you need to come on here to get people to do your homework for you, I think you should find another course.

Answer 2

The way to do this is to equate the "centrifugal force", mv^2/r, with the gravitational force, which in this case is equal to Gm^2/(2r)^2

You can do this either by looking up G in SI units and converting all the other data to similar units, or more elegantly by calculating the value of G in AU using data for the Sun-Earth system.