Final answer:
Curvature refers to the shape of a surface affecting light focus, while refraction is the bending of light when it passes from one medium to another.
Step-by-step explanation:
The difference between curvature and refraction lies in their definitions and related optical phenomena. Curvature refers to the bend or curve of a surface, like that of a lens, which affects how it focuses light. Refraction, on the other hand, is the change of direction (or bending) of a light ray when it passes from one medium to another with a different refractive index.
Reflected light bounces off surfaces at the same angle at which it hits them, following the law of reflection. In contrast, refracted light is bent due to the change in speed when it travels from one medium to another, as described by Snell's law. For example, a straw appears bent where it enters water, illustrating refraction.
Both reflection and refraction are fundamental concepts in optics, affecting everything from the use of mirrors to the formation of images by lenses.