How we worked it out
Updated as you change the numbers.
- f = c ÷ λ; E = h × f. c = 299,792,458 m/s; h = 6.62607015 × 10⁻³⁴ J·s.
Method and assumptions
Both constants are exact in the SI since 2019.
Questions
What is the photon energy of 550 nm green light?
About 2.254 eV (545 THz).
Sources
Method and figures checked on . Every worked answer on this page is covered by an automated test. Found a mistake? Tell us.