Q12 of 25 Page 11

A student is unable read the blackboard placed at a distance of approximately 4 m from him. Name the defect of the vision the boy is suffering from. ( CBSE 2015, 2014)

As the student is unable to see clearly the words written on the blackboard at a distance of 4 m, the student is suffering from myopia or near-sightedness.

This defect is corrected with concave lens of suitable focal length is used. The image is allowed to form at the retina by using a concave lens of suitable power.


Ray diagrams for the (i) defect of vision and (ii) for its correction:


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