Final answer:
Parallel paraxial rays approach a converging lens and converge at the lens's focal point, located on the opposite side from where the rays enter.
Step-by-step explanation:
When parallel paraxial rays approach a converging lens, they converge at the focal point of the lens on the other side. This is a fundamental property of converging lenses and is due to the refraction of light as it passes through the lens. The focal point is the specific point at which light rays meet after passing through the lens. Converging lenses have the ability to bring parallel rays to a focus owing to their shape and the refractive properties of the material they're made from.
The focal length, denoted by the symbol f, is the distance from the center of the lens to the focal point, and it is a key parameter in determining where the rays will converge after passing through the lens. Understanding this concept is crucial in optical devices such as cameras, telescopes, and eyeglasses, as it helps to determine the image formation characteristics of the lens.