How does a standard two-pan balance yield the same mass reading regardless of its planetary location?

Answer

The gravitational factor ($g$) is applied equally and cancels out during comparison

A true mass balance works by comparison to known standards; because gravity acts equally on both the unknown mass and the known standards, the gravitational factor cancels out during the equilibrium achievement.

How does a standard two-pan balance yield the same mass reading regardless of its planetary location?
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