Why is the risk of sunburn greatest from 11AM to 3PM?

The risk of sunburn is greatest from 11 AM to 3 PM because this period coincides with the sun's highest position in the sky, resulting in the most intense ultraviolet (UV) radiation. During these hours, the UV rays have a shorter path through the atmosphere, leading to increased exposure on the skin. Additionally, factors such as reflection from surfaces like water, sand, and concrete can further amplify UV radiation during this time, heightening the risk of sunburn.