Answer:
λ = 555.55 nm
Step-by-step explanation:
the photon energy equation
∴ h = 6.626 E-34 J*s.....Planck's constant
∴ f = 5.4 E14 s-1
⇒ E = (6.626 E-34 J*s)(5.4 E14 s-1) = 3.578 E-19 J
∴ E = hc/λ
⇒ λ = hc/E
∴ c ≅ 3.0 E8 m/s
⇒ λ = ((6.626 E-34 J*s)(3.0 E8 m/s))/(3.578 E-19 J)
⇒ λ = (5.555 E-7 m)×(1 E9 nm/m) = 555.55 nm