Convert Nail (Cloth) (nail) to Bohr Radius (a₀) instantly.
About these units
Nail (Cloth) (nail)
The nail is another small unit in cloth measurement, roughly 2.1 cm (0.83 inches), sometimes used interchangeably with the finger in English tailoring. The nail allowed fine precision in textile cutting, marking, and assembly. Its practical relevance lay in breaking down larger units like the yard or ell into smaller, manageable increments suitable for artisans. Though obsolete in modern industry, the nail continues to appear in historical accounts, tailoring manuals, and legal documents concerning cloth trade in England.
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.