Convert fingerbreadth to Electron radius (classical) Online | Free Length Converter

Fingerbreadth

A fingerbreadth is a traditional unit of length based on the width of a human finger, often used in historical and informal measurements. It typically measures about ¾ inch (approximately 19 millimeters), though it can vary depending on the person and context.

Fingerbreadths were commonly used in tailoring, medicine, and everyday life to estimate small lengths before standardized units became widespread.

Key points:

• 
  

  Approximately ¾ inch (19 mm)

  
  
• 
  

  Based on the width of a finger

  
  
• 
  

  Used in historical measurements and everyday approximations

  
  
• 
  

  Part of body-based units like handbreadth and span

  
  

Fingerbreadth remains a handy reference for rough estimates even today.

Classical Electron Radius

The classical electron radius is a theoretical length scale associated with the electron, derived from classical electromagnetism. It represents the size of a hypothetical sphere where the electron’s electrostatic energy equals its rest mass energy.

• 
  

  Its value is approximately 2.818 × 10⁻¹⁵ meters (about 2.8 femtometers).

  
  
• 
  

  Calculated using fundamental constants: the electron charge, mass, and the speed of light.

  
  
• 
  

  It is not the actual physical size of the electron (which is considered point-like in quantum mechanics), but a useful scale in classical physics.

  
  
• 
  

  Used in scattering theory and classical electron models.

  
  

Key facts:

• 
  

  Classical electron radius ≈ 2.818 × 10⁻¹⁵ m

  
  
• 
  

  Represents an electromagnetic length scale, not a physical size

  
  
• 
  

  Important in classical models of electron behavior

  
  

This radius helps bridge classical and quantum views of particle physics.