Convert Mile (mi) to Electron Radius (re) instantly.
About these units
Mile (mi)
The mile, equal to 5,280 feet, is a legacy of a long history of measurement stretching back to Roman times. Its ancestor, the Roman "mille passus" (thousand paces), established a rough distance of 1,480 meters, which evolved through medieval and early modern Europe into various regional miles. The English statute mile was standardized in 1593 and survives today in the United States, the United Kingdom (for roadways), and a few other territories. Despite being a non-metric unit, the mile remains deeply embedded in cultural and infrastructural systems. Road networks in the US are laid out with mile markers; athletic events include the famed "one-mile run"; and many people intuitively judge driving distances in miles. Aviation and international travel sometimes reference statute miles, though nautical miles dominate in navigation. Its long history and familiarity keep the mile relevant even in a metric world.
Electron Radius (re)
The classical electron radius, approximately 2.818 × 10⁻¹⁵ meters, is a theoretical value derived from classical electromagnetic theory rather than an actual measured size. It represents the radius a charged sphere would need to have in order for its electrostatic self-energy to equal the electron's rest energy. Although electrons are now understood to be point-like or extremely small compared to this radius, the classical electron radius remains useful in scattering theory, especially in calculations involving Thomson scattering — the elastic scattering of electromagnetic radiation by free electrons. Thus, while not a physical dimension of the electron, the classical radius serves as a meaningful parameter in specific areas of physics and retains importance in radiation modeling and plasma physics.