A lead ingot was suspended on one side of the balance beam, and a piece of glass was suspended on the other.

A lead ingot was suspended on one side of the balance beam, and a piece of glass was suspended on the other. Will the balance be preserved if both lead and glass are completely immersed in water? If not, which shoulder will you pull?

Equilibrium will be preserved if the sum of the moments of forces is equal to 0. The moment of force is the product of force by the length of the arm. at the rocker arms are meant equal lengths, and the mass of the two bodies is the same, hence the force of gravity is equal. The moments of forces are equal, and “they are trying to twist the rocker arms in different directions”, then the sum of the moments is equal to 0 => the balance is maintained.