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atarr3
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Homework Statement
Two masses, m and 2m, orbit around their CM. If the orbits are circular, they don't intersect. But if they are very elliptical, they do. What is the smallest value of eccentricity for which they intersect?
Homework Equations
[tex]c=\sqrt{a^{2}+b^{2}}=\frac{k\epsilon}{1-\epsilon^{2}}[/tex] where a and b are the lengths of the semi-major and semi-minor axis, respectively. And [tex]k=\frac{L^{2}}{m\alpha}[/tex]
The Attempt at a Solution
I'm having trouble visualizing this problem with elliptical orbits. When they're circular it's like they are concentric circles. Mass 2m has an orbital radius of 1/3 distance of separation and mass m has an orbital radius of 2/3 distance of separation. I have equations that relate eccentricity to the lengths of the semi-major and semi-minor axis, but I'm confused as to how I can actually find those values. I'm also confused as to when the orbits intersect. Does this occur when the semi-major/semi-minor axis of one orbit equals that of the other? I'm just looking for a little guidance in this problem. The only thing I know is that the CM is a focus for both elliptical orbits. Thanks guys!