1. What kind of defect in vision is she suffering from?

CBSE Class 10 CBSE Class 10 Science
1

Noopur needs a lens of power - 4.5D for correction of her vision.
1.What kind of defect in vision is she suffering from?
2.What is the focal length and nature of the corrective lens?
3.Draw ray diagrams showing the

  • defected eye and
  • correction for this defect.
  • Draw ray diagram

4.What are the causes of this defect?

2

Power of lens = - 4.5 D.
1.She is suffering from Myopia or near sightedness.
2.Myopia can be corrected by using concave lens of suitable power. Here, - 4.5 D.

image

So, focal length of corrective concave lens is - 0.22 cm = f.

3
image

4 This defect may arise due to-

  • excessive curvature of the eye lens
  • elongation of the eye ball.