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## Homework Statement

What is the magnitude of the net gravitational force on the m2=5kg mass? Assume m1=25kg and m3=15kg.

https://session.masteringphysics.com/problemAsset/1383524/6/13_P28.png

## Homework Equations

F=GMm/r^2

## The Attempt at a Solution

First I find the angle between m1 and m2 which is arctan(10/20)=27

Find the force m3 on m2 which is

F23=Gm2m3/0.22^2(cos27i-sin27j)=8.91*10^-9Ni-4.54*10^-9Nj

There also a force acting m2 on m1 which is

F21=-Gm1m2/0.2^2=-2.09*10^-7Nj

the net force, I do Fnet=sqrt((8.91*10^-9Ni)^2+(-2.09*10^-7Nj-4.54*10^-9Nj)^2)=2.137*10^-7N

However, the answer I got is incorrect.

can anyone tell me where I did wrong?

Thanks![/B]