Electron Radius (Classical) to Kilometer Converter
Unit Converter
Instant · Precise · Universal
32 units available
6 categories total
How to Convert Electron Radius (Classical) to Kilometer
To convert to meters: multiply by 2.8179403262 × 10⁻¹⁵.
re = e²/(4πε₀mec²) ≈ 2.8179 × 10⁻¹⁵ m, where e is electron charge and me is electron mass.
For example, 1 Electron Radius (Classical) (re) = 2.817940e-18 Kilometer (km).
Electron Radius (Classical) to Kilometer — Common Values
| Electron Radius (Classical) (re) | Kilometer (km) |
|---|---|
| 0.1 | 2.817940e-19 |
| 0.5 | 1.408970e-18 |
| 1 | 2.817940e-18 |
| 2 | 5.635881e-18 |
| 5 | 1.408970e-17 |
| 10 | 2.817940e-17 |
| 25 | 7.044851e-17 |
| 50 | 1.408970e-16 |
| 100 | 2.817940e-16 |
| 500 | 1.408970e-15 |
| 1000 | 2.817940e-15 |
About Electron Radius (Classical) (re)
Definition
The classical electron radius is a theoretical length scale derived from the electron's charge and mass, approximately 2.818 × 10⁻¹⁵ meters.
Mathematical Relationship
re = e²/(4πε₀mec²) ≈ 2.8179 × 10⁻¹⁵ m, where e is electron charge and me is electron mass.
Conversion Formula
To convert to meters: multiply by 2.8179403262 × 10⁻¹⁵.
Practical Applications
Used in calculating X-ray and gamma-ray scattering probabilities off electrons (Thomson and Compton scattering).
Interesting Facts
Despite its name, the electron is a point particle in quantum theory — the 'classical radius' is a theoretical construct, not the electron's actual size.
Common Mistakes
Assuming this is the actual physical size of the electron — quantum mechanics shows the electron has no measurable size.
Educational Tips
Think of it as the scale at which classical electromagnetic self-energy equals the electron's mass-energy.
About Kilometer (km)
Definition
The kilometer is a unit of length equal to 1,000 meters, commonly used to express distances between geographic locations.
Mathematical Relationship
1 km = 1,000 m = 100,000 cm = 0.621371 miles. There are 1.60934 km in one mile.
Conversion Formula
To convert km to miles: multiply by 0.621371. To convert miles to km: multiply by 1.60934.
Practical Applications
Road signs, marathon distances (42.195 km), GPS navigation, geographic mapping, and aviation flight distances.
Interesting Facts
A marathon is 42.195 km. The circumference of Earth is approximately 40,075 km at the equator.
Common Mistakes
Assuming 1 km = 1 mile. A kilometer is only about 62% of a mile. Also, speed: 100 km/h ≈ 62 mph, not 100 mph.
Educational Tips
Quick approximation: multiply km by 0.6 to estimate miles, or multiply miles by 1.6 for km.