Pulley Question: Clarifying Fnetx Calculation

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The discussion clarifies the calculation of net forces in a pulley system involving two blocks with differing weights. The key equation established is Fnety = Fw - T, where Fw represents the weight of the block and T is the tension in the rope. This formulation ensures that the net force results in a positive acceleration for both blocks, aligning with the standard coordinate system where upward forces are positive. The confusion arises from the interpretation of the free body diagram, emphasizing the importance of consistent directional conventions in physics calculations.

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http://img135.imageshack.us/img135/3314/yeaheg1.th.png

I was wondering if someone could clarify this for me.
(this system of accelerating, the block on the right is heavier)
I know that Fnetx = T.

However, I'm a little confused about why Fnety should be Fw - T as opposed to T - Fw

When I was doing the free body diagram, for the y coord: T points up and Fw points down, so I was thinking since the standard coord system has up as +y and down as -y then Fnety = T - Fw, unfortunately it seems that it's necessary to reverse that.
 
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probably reversed so that acceleration comes out as a positive value for both blocks.
 

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