weighings

Weighing is the procedure of determining the gravitational force exerted on an object. In everyday usage, weight is often treated as mass, but scientifically weight is a force measured in newtons and mass is measured in kilograms. At Earth's surface, weight roughly equals mass times the standard gravitational acceleration, though exact values vary with location.

Common weighing devices include balance scales, which compare an unknown mass to known reference weights on two pans; beam scales and spring scales, which translate force into a readable scale; and electronic balances, which use load cells to convert force into an electrical signal. Modern laboratory balances are highly precise and can measure milligram or microgram masses with electronic readouts. Tare procedures remove the weight of containers from measurements.

Units: weight is a force and uses newtons (N); mass uses kilograms (kg). In commerce and lay language, weight is often expressed in kilograms or pounds, reflecting mass rather than force. Readings can be expressed in the chosen unit, with clear distinction between mass and weight in scientific contexts.

Calibration and accuracy: weighings require calibration with certified standard weights and traceability to national or international standards. Factors such as temperature, air buoyancy, vibration, and instrument drift can affect accuracy and must be controlled. Repeated measurements improve precision and help detect systematic error.

Applications: weighings are central to retail, manufacturing, shipping, laboratories, and research. Weighing practices are governed by metrology standards to ensure reliability and interoperability across institutions and industries.