Convert Electron Radius (re) to Ell (ell) instantly.
About these units
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.
Ell (ell)
The ell is a traditional European unit of length, varying between 45–70 cm depending on the region. It originated from the forearm or arm length and became standardized in many countries for measuring cloth and textiles. In commerce, the ell simplified transactions, allowing merchants to describe fabric lengths efficiently. In tailoring, it offered a consistent basis for cutting and patterning clothing. The unit was essential in guild systems, where precision and repeatability in textile production were critical. While largely obsolete today due to the metric system, the ell remains significant for historians, textile scholars, and anyone studying pre-modern European commerce and craft practices.