Suppose you had two bars with mass m and length L and there were parallel to each other, along the same line and a distance d apart. How do we calculate the force between them?(adsbygoogle = window.adsbygoogle || []).push({});

______________ ______________

|-----L--------| |------d-------| |-------L-------|

I figured out how to do it if it is a bar and point mass. Then I thought maybe if add up the particles forces along the line but I couldn't get it to work out.

Density = E = M/L; dm = E dr

F = G(massofparticle)E dr/r^2 = G(mass of particle)(1/r)

mass of partlcle = dm = E dr

And then evaluate the integral again to get the force for the sum of particles but I don't think that method works.

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# Homework Help: Force of gravity between 2 bars

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