$A$ convex lens can be used to correct long-sightedness (hypermetropia).

In the eye of a person suffering from hypermetropia (farsightedness),where is the image of a nearby object formed?

$A$ 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.

Which of the following phenomena of light are involved in the formation of a rainbow?

How is astigmatism corrected?

When a beam of white light is passed through a prism,violet colour bends the most and red colour the least.