If you know yellow field is a quarter density respect than blue.
You note circumferenceses are orizzontally in equilibrium,but vertical not.
If you put a weight (in red-the the thin red line into yellow),that win vertical opposite force of the blue liquid,there is a torque on circumference.this is sold.
My question is "will be a place where this red weight" is in equilibrium with the system? I don't know.... answer me please
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