Photon energy from wavelength
Using hc ≈ 1,240 eV·nm, what is the energy of a 500 nm photon?
Answer B: explanation for every choice
A
This inverts the ratio (λ/hc).
B
Correct. E = hc/λ = 1,240/500 = 2.48 eV.
C
This uses 50 nm instead of 500 nm.
D
This multiplies hc by λ.
TakeawayE = hc/λ. hc ≈ 1,240 eV·nm.
Equation usedPhoton energy
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