(adsbygoogle = window.adsbygoogle || []).push({}); Two baseballs, each with a mass of 0.158 kg, are separated by a distance of 400 m in outer space. If the balls are released from rest, what speed do they have when their separation has decreased to 270 m? Ignore the gravitational effects from any other objects.

I keep on using the conservation of energy equation, but nothing seems to give, I feel like i'm missing a step, Please help...

This is what I've done so far

Ei=Ef

1/2mvi^2-(Gm1m2/ri)=1/2mvf^2-(Gm1m2/rf)

if this is the right equation....

KEi obviously = 0, how to I get rid of the mass(m) in the KEf, I can't cancel it out since there are 2 masses involved, am I right?

value for G = 6.67x10^-11

Thanks for the help.

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# Gravity: Energy Conservation

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