Convert Rod (US Survey) (rd (US)) to Bohr Radius (a₀) instantly.
About these units
Rod (US Survey) (rd (US))
The US Survey Rod equals 16.5 US Survey Feet (~5.0292 meters). Like the chain and furlong, it serves as a subdivision of larger units, maintaining consistency with historic Gunter-based measurements. Surveyors historically used rods to measure short distances, delineate boundaries, and calculate acreages. Its simple relationship to chains and furlongs made it practical for field measurements without complex arithmetic. Today, the US survey rod primarily appears in historical records, legal surveys, and when referencing pre-metric property data, providing continuity between older and modern surveying conventions.
Bohr Radius (a₀)
The Bohr radius, equal to approximately 5.29177 × 10⁻¹¹ meters, is the most probable distance between the electron and nucleus in the ground state of hydrogen according to the Bohr model. While modern quantum mechanics has evolved far beyond the Bohr model, the radius remains a remarkably accurate approximation for average atomic dimensions. The Bohr radius acts as a natural "yardstick" for the size of atoms and is frequently used in atomic physics and quantum chemistry. Many atomic properties — orbital sizes, electron probability distributions, and energy levels — are conveniently expressed in multiples of the Bohr radius. Because it reflects fundamental constants, including Planck's constant and the electron charge, the Bohr radius also appears in theoretical analyses of physical systems and helps unify atomic physics concepts across different contexts.