Question

20. A myopic person uses specs of power - 0,5D. What is the distance of far point of his eye?
Give full solution​

Answer 1

Power=0.5 D

Focal length =1/0.5 = 10/5 =2m

Lens formula= 1/v - 1/u = 1/f

given f = 2m=200cm

We know that near point of an eye is 25 cm

now put the values in the formula

f=200

v=-25cm

1/-25 -1/u=1/200

1/u=1+8/200

u=200/9