Ton (t)
Definition: The ton (symbol: t), also known as the metric ton, is a unit of mass in the International System of Units (SI). It is defined as exactly 1,000 kilograms or 2,204.62 pounds. The ton is commonly used in industry and commerce for measuring large quantities of goods.
History/origin: The ton has been used as a unit of measurement since the 13th century. It was originally defined as the weight of a large cask of wine. The modern metric ton was standardized in 1795 as exactly 1,000 kilograms.
Current use: The ton is used globally in shipping, construction, and manufacturing for measuring the mass of large objects and quantities of materials.
Kilogram (kg)
Definition: The kilogram (symbol: kg) is the base unit of mass in the International System of Units (SI). It is defined by taking the fixed numerical value of the Planck constant h to be 6.62607015×10⁻³⁴ when expressed in the unit J·s, which is equal to kg·m²·s⁻¹.
History/origin: The kilogram was originally defined in 1795 as the mass of one liter of water. In 1889, the International Prototype of the Kilogram (IPK) was created. In 2019, the kilogram was redefined in terms of fundamental physical constants.
Current use: The kilogram is used globally in science, engineering, and commerce. It is the standard unit of mass in most countries around the world.