Convert Stone (US) (st (US)) to Muon Mass (mᵤ) instantly.
About these units
Stone (US) (st (US))
The US stone was an informal and nonstandardized unit occasionally used in the 19th century, with no single agreed-upon value. Unlike the British stone (14 pounds), the US stone varied regionally and by trade context, typically ranging from 12 to 16 pounds, depending on the commodity and location. Farmers, butchers, and merchants sometimes used stones to weigh produce, meat, or livestock, but the lack of uniform regulation prevented it from becoming an official or widely adopted unit. Today, the US stone is entirely obsolete, but references to it appear in historical American trade documents, agricultural records, and pre-standardization weight systems. It serves as a reminder of the diversity of early American measurements before the widespread adoption of the avoirdupois pound.
Muon Mass (mᵤ)
The muon is a heavier cousin of the electron, with a mass of about 1.8835316 × 10⁻²⁸ kilograms, roughly 207 times more massive than the electron. Because the muon behaves like an electron but with much greater mass, it offers unique opportunities for probing fundamental physics. Muonic atoms—where a muon replaces an electron—allow extremely precise measurements of nuclear size due to the muon's tighter orbit. Muons are also produced naturally in Earth's atmosphere from cosmic rays and are widely studied in particle accelerators. Research into muon behavior has led to major discoveries, and the muon mass continues to attract interest in tests of physics beyond the Standard Model.