What is K in Planck's law?

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Tags

1. #temperature
2. #electromagnetic
3. #radiation
4. #given
5. #black
6. #density
7. #planck
8. #equilibrium
9. #between
10. #describes
11. #spectral
12. #there
13. #emitted
14. #matter
15. #environment
16. #thermal
17. #energy