# luminous efficacy of a source

> ratio between the emitted luminous flux and the electrical power consumed by a light source

**Wikidata**: [Q3425218](https://www.wikidata.org/wiki/Q3425218)  
**Source**: https://4ort.xyz/entity/luminous-efficacy-of-a-source


## References

1. ISO 80000-7:2019 Quantities and units — Part 7: Light and radiation