Which type of lens would be beneficial for someone who is short sighted?

For someone who is short sighted, also known as myopia, a concave lens is beneficial because it helps to diverge light rays before they enter the eye. In short sightedness, the eye focuses images in front of the retina rather than on it, making distant objects appear blurry. A concave lens works by spreading the light rays out, which effectively allows the eye to focus these rays onto the retina, making distant objects clearer.

This adjustment helps alleviate the vision problems associated with myopia, enabling the individual to see further away more clearly. In contrast, other types of lenses, like convex lenses, bend light rays together and are typically used for correcting farsightedness, not short sightedness. Flat lenses have no bending ability and don't correct vision issues. Prism lenses are used for specific vision problems related to eye alignment rather than for correcting short sightedness directly.