what is it exactly?(adsbygoogle = window.adsbygoogle || []).push({});

and in my book they had an equation

F = (4)(pi)^2(m)(r)/T^2

then they said by using keplers law... they arrived to a new equation that relates the gravitational force exerted by the sun which is...

F = m/r^2

If Keplers law says T = r^3/2 how in the heck did they go from F = (4)(pi)^2(m)(r)/T^2

to F = m/r^2 by substituting T for r?????

Where did (4)(pi)^2(r) go ????????

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# Homework Help: Keplers law

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