UV light causes sunburn due to its higher photon energy compared to visible light, which does not have enough energy to damage organic molecules in the skin. The discussion highlights the relationship between photon energy and its ability to cause damage, referencing the photoelectric effect as a parallel. It emphasizes that the frequency of light, rather than intensity, determines its potential to induce reactions in materials. The damage from UV light leads to sunburn, while visible light lacks the necessary energy to trigger similar effects. Understanding these principles clarifies why UV exposure is harmful to skin.
