In myopia,what happens to the power of the eye lens?

$(i)$ What is the least distance of distinct vision for a normal eye?
$(ii)$ Does the above distance increase or decrease for a long-sighted eye (hypermetropia)? Give a reason for your answer with a diagram.

$A$ person suffering from an eye defect uses lenses of power $-1 \,D$. Identify the eye defect. Draw a suitable diagram to illustrate how this type of lens corrects the defect. Give the nature of the corrective lens to be used. Also,calculate the focal length of the corrective lens.

How can you identify the type of vision defect a person is suffering from by physically touching their spectacles?

What is the number of receptors contained in the retina?

When do we consider a person to be myopic or hypermetropic? Explain how the defects associated with a myopic and hypermetropic eye can be corrected.