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autodidude
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Homework Statement
From K&K's 'Intro to Mechanics'
Find the shortest possible period of revolution of two identical gravitating solid spheres which are in circular orbit in free space about a point midway between them.
Homework Equations
The Attempt at a Solution
So I figured the gravitational force exerted on each sphere by the other would be
[tex]F=\frac{2mg}{r^2}[/tex]
according to Newton's law of gravitation (m being each sphere's mass). This force would be providing the centripetal acceleration that's keeping them going in a circle so the angular velocity can't exceed a certain value and this is related to the period of revolution.
[tex]F_c=\frac{2mG]{r^2}=m\frac{v^2}{r}[/tex]
∴[tex](\frac{2G}{r})^{1/2}=v[/tex]
So plugging that into [tex]T=\frac{\omega}{2\pi}[/tex] gives me [tex]T=(\frac{G}{2\pi^2r^3})^{1/2}[/tex]
Is this correct? If not, am I at least on the right track?
Thanks in advance