$A$ person is unable to read a book clearly when kept at a distance of $25 \,cm$ from his eye. Name the defect. How can it be corrected? Draw ray diagrams for $(i)$ defective eye $(ii)$ corrected eye and explain them.

(N/A) The defect is Hypermetropia,also known as long-sightedness. In this condition,the near point of the eye shifts further away than the normal $25 \,cm$.
It can be corrected by using a convex lens of suitable focal length,which converges the light rays from the object at $25 \,cm$ to the eye's actual near point $(N')$,allowing the eye to focus the image on the retina.
$(i)$ Defective eye: Rays from an object placed at the normal near point $(N = 25 \,cm)$ are focused behind the retina because the eye's near point has shifted to $N'$.
$(ii)$ Corrected eye: $A$ convex lens is placed in front of the eye. It forms a virtual image of the object (placed at $N$) at the eye's actual near point $(N')$. The eye then focuses this image onto the retina.