What is short-sightedness ? State the two causes of short-sightedness (or myopia). With the help of ray diagrams, show:

(i) the eye-defect short-sightedness.


(ii) correction of short-sightedness by using a lens.


The defect of vision due to which a person can see nearby objects clearly but cannot see distant objects clearly is known as short-sightedness.

The two of its causes are :-


1) Excessive curvature of the eye lens


2) Elongation of the eyeball.


Its ray diagram can be shown as :-


(i)



(ii) The 3rd diagram shows the correction of short-sightedness by using a lens.


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