Ephoton = h c / Ephoton = h c / (514 nm) = 3.86468×10-19 J Emin = Ephoton * (# of photons) Emin / Ephoton = # of photons # of photons = 2×10-17 J / 3.86468×10-19 J = 51.7507 52 Solution Ephoton = h c / Ephoton = h c / (514 nm) = 3.86468×10-19 J Emin = Ephoton * (# of photons) Emin / Ephoton = # of photons # of photons = 2×10-17 J / 3.86468×10-19 J = 51.7507 52.