Question

Ex:4) An opthalmologist prescribed 1.5 D lens to Roja. So what do you understand from this find f




Human eye and colourful world
prescription ?
Here the power of lens is positive it mean ho
osted Bi-convex lens.​

Answer 1

Answer:

lens having a power +1.5 D will have a focal length of

P =1/f

+1.5 D = 1/f

f = 1/1.5 = 2/3 = + 0.67 m.

The focal length is + 0.67m.

The nature of lens is converging type or convex lens.

The defect of the eye is Hyperopia or far-sightedness.

Answer 2

Explanation:

here the power of lens is positive it means he suggested by convex lens so Roja is suffering from hypermetropia

power of lens D is equals to 100 by f or f is equals to 100 by D is equals to 100 by 1.5 is equals to 1000 by 150 is equals to 20 by 3

but f is equals to 25 x by x minus 25

25 x by x minus 25 is equals to 20 by 3

75 X is equals to 20X - 500

55 X is equals to minus 500

X is equals to minus 500 by 55 is equals to minus 10

so she is not able to see below 10 cm . ( It was happen in a real life situation because least distance point for distant vision is 25 CM ).

hope all of you understood.

thank you all