Bonjour,
λ = 1.10⁻⁶ m et E(impulsion) = 0,1.10⁻⁶ J
1) ν = c/λ = 3.10⁸/1.10⁻⁶ = 3.10¹⁴ Hz soit 300 THz
2) infrarouge
3) E = h x ν = 6,63.10⁻³⁴ x 3.10¹⁴ ≈ 2.10⁻¹⁹ J
4) n = E(impulsion)/E = 0,1.10⁻⁶/2.10⁻¹⁹ ≈ 5.10¹¹ photons
