The photon energy of light of wavelength 600 nm is closest to

Explanation

Using the convenient result that photon energy in electron volts is about 1240 divided by the wavelength in nanometres, 1240 over 600 gives roughly 2 eV. Visible photons all lie between about 1.6 and 3.1 eV, which is a useful range to remember as a check. Values of hundreds of electron volts belong to X rays.