http://session.masteringphysics.com/problemAsset/1125570/2/Walker4e.ch12.Pr042.jpg(adsbygoogle = window.adsbygoogle || []).push({});

use this image for help

a. Consider the four masses shown in the figure . Find the total gravitational potential energy of this system.

b. How does your answer to part A change if all the masses in the system are doubled?

c. How does your answer to part A change if, instead, all the sides of the rectangle are halved in length?

I'm absolutely lost in this problem. I know that U=-GmMe/r

where Me is the mass of earth.

r= radius

However, I don't know how to apply that to so many different masses.

Please help and explain?!

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# Homework Help: Find the total gravitational potential energy of this system?

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