tweeschalenbalans

A tweeschalenbalans, also known as a beam balance or equal-arm balance, is a weighing instrument used to measure mass by comparing an unknown mass with a known mass. It consists of a horizontal beam that is pivoted at its center, typically on a fulcrum. Two pans or dishes are suspended from the ends of the beam. When the tweeschalenbalans is used, the object of unknown mass is placed on one pan, and known masses (often in the form of calibrated weights) are added to the other pan until the beam is balanced. When the beam is horizontal, the masses on both pans are equal. This principle of leverage is fundamental to its operation.

The accuracy of a tweeschalenbalans depends on the precision of its construction, particularly the beam and fulcrum, as well as the accuracy of the known masses used. Older and simpler versions might be found in educational settings or for approximate measurements, while more precise laboratory models are used in scientific research and analytical chemistry. The sensitivity of the balance indicates how small a difference in mass can be detected. The tweeschalenbalans is distinct from spring scales or electronic balances, which measure weight (the force of gravity) rather than mass directly. Its use relies on the fundamental law of moments.