In the United Kingdom, a "hundredweight" (abbreviated as cwt) is a unit of weight or mass used in various industries and commerce. However, it's important to note that the UK hundredweight is different from the US hundredweight in terms of its value.
In the United Kingdom:
1 hundredweight (UK) = 112 pounds (lbs)
So, while the US hundredweight is equal to 100 pounds, the UK hundredweight is equal to 112 pounds. This difference in value is important to be aware of when dealing with weights and measurements, especially in international trade or when comparing British measurements to those used in the United States or other countries.
The kilogram (kg) is the base unit of mass in the International System of Units (SI). It is defined as the mass of the International Prototype of the Kilogram (IPK), a platinum-iridium cylinder kept at the International Bureau of Weights and Measures (BIPM) in France.
Until May 20, 2019, the kilogram was defined by the physical prototype, but as part of the redefinition of the SI units, the kilogram was redefined in terms of fundamental constants. Since that date, the kilogram is defined by fixing the numerical value of the Planck constant (h) to be exactly 6.62607015 x 10^-34 joule-seconds.
This redefinition ensures that the value of the kilogram is now based on a constant of nature rather than relying on a physical object that could potentially change over time. It allows for a more precise and stable definition of the kilogram and other SI units.