Question

A person is unable to see objects nearer than 50cm. HE wants to read a book placed at a distance of25 cm. Find the nature, focal length and power of the lens he requires for his spectacles.

Answer 1

HEY DEAR ...

This person has defect of Hypermetropia which is farsightedness that means the image formed at beyond the retina so it requires to a convergent lens to get focussed at retina

Now corrective measure is

u= - 25 cm

v= -50 cm

1/f= 1/v- 1/u

1/f= 1/-50 - 1/-25 = -1+2/50 = 1/50

f= 50 cm

p=1/f

p=1/50

=0.02cm = 0.0002 D

HOPE , IT HELPS ...

Answer 2

Answer:

This person has defect of Hypermetropia which is farsightedness that means the image formed at beyond the retina so it requires to a convergent lens to get focussed at retina

u = -25 cm

v= -50cm

1/f = 1/v - 1/u

=  1/-50 - 1/-25

f = 50

p = 1/f

p = 100/50

p = 2D

focal length = 50 cm

power = 2D hope it helped pls mark as brainlist answer