Monochromatic light of frequency 6 × 1014 Hz is produced by a laser source. The energy of photon of light is:

3.98 × 10-19 J 39.8 × 10-19 J 3.12 × 10-20 J 2.24 × 10-20 J

3.98 × 10-19 J

Energy of a photon is $ E = h\nu = 6.63\times 10^{-34}\times 6\times 10^{14} = 3.98\times 10^{-19} J$