A short-sighted person has a near point of 15 cm and a far point of 40 cm.

(a) Can he see clearly an object at a distance of:


(i) 5 cm ? (ii) 25 cm ? (iii) 50 cm ?


(b) To see dearly an object at infinity, what kind of spectacle lenses does he need ?

(a) i) A short-sighted person has a near point of 15 cm and a far point of 40 cm. He cannot see an object clearly when it is at a distance of 5cm.

ii) A short-sighted person has a near point of 15 cm and a far point of 40 cm. He can see an object clearly when it is at a distance of 5cm.


iii) A short-sighted person has a near point of 15 cm and a far point of 40 cm. He can see an object clearly when it is at a distance of 50cm.


(b) To see clearly an object at infinity spectacles should must have a concave lenses.


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