Ultraviolet light causes sunburns, whereas visible light, even of greater intensity, does not. Why?
Ultraviolet (UV) light can cause sunburns because it is more energetic than visible light. To understand why UV light can cause sunburns while visible light does not, let me explain the basics of how light interacts with our skin.
Light is made up of particles called photons, and each photon carries a certain amount of energy. UV light has higher energy photons compared to visible light. When UV photons reach our skin, they can penetrate deeper into our tissues and interact with the molecules present, including DNA molecules.
UV light can directly damage our skin cells' DNA, leading to cell mutations and potentially causing skin cancer. Additionally, the interaction of UV light with skin cells triggers an inflammatory response, which we perceive as a sunburn.
On the other hand, visible light has lower energy photons that do not carry enough energy to directly damage our DNA or cause sunburn. Although visible light can heat up our skin and may cause a sensation of warmth, it does not have the same harmful effects as UV light.
To protect ourselves from UV light and prevent sunburns, it is important to use sunscreen or protective clothing that can block or absorb UV radiation.
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The frequency of uv light is higher than visible, therefore, it has more energy.