# impedance of vacuum

> physical constant relating the magnitudes of the electric and magnetic fields of electromagnetic radiation travelling through free space

**Wikidata**: [Q269492](https://www.wikidata.org/wiki/Q269492)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Impedance_of_free_space)  
**Source**: https://4ort.xyz/entity/impedance-of-vacuum


## References

1. Freebase Data Dumps. 2013
2. [CODATA recommended values of the fundamental physical constants: 2014](https://physics.nist.gov/cgi-bin/cuu/Value?z0)
3. IEC 80000-6:2022 Quantities and units — Part 6: Electromagnetism
4. International Electrotechnical Vocabulary