Answer :
Final answer:
The lower calibration bar of a balance beam scale is divided into units of mass, typically in grams, to provide a reference point for measuring the mass of an object.
Explanation:
In a double-pan mechanical balance, the lower calibration bar is typically divided into units of mass. These units can vary depending on the scale, but they are often marked in grams. For example, the divisions on the bar might go from 0 grams to 100 grams, with smaller subdivisions in between.
The purpose of these divisions is to provide a reference point for measuring the mass of an object. By placing known masses on one pan and an object of unknown mass on the other pan, you can determine the unknown mass by adjusting the position of the calibration bar until the pans are balanced.
