Question

Draw the figure for given situation of eye ball, suppose an object is at 25 cm before eye and minimum focal length of eye is 2.27cm.

Answer 1

Explanation:

Given that,

Object distance u = -25 cm

Focal length f = 2.27

Using lens formula

$\dfrac{1}{f}=\dfrac{1}{v}-\dfrac{1}{u}$

$\dfrac{1}{v}=\dfrac{1}{2.27}-\dfrac{1}{25}$

$\dfrac{1}{v}=\dfrac{4}{10}$

$v= \dfrac{10}{4}$

$v= 2.5 cm$

The distance of the image is greater than the focal length.

So, The defect is hypermetropia.

Therefore,we will use the convex lens for correcting the defect.