Question

noopur needs a lens of power -4.5 D for correction of our vision
1)what kind of defect in vision she suffering from?
2)what is the focal length and nature of the corrective lens?
3)draw a diagram showing the defected eye and currection of the deffect
4) what are the causes of this defect

Answer 1

1)she is suffering from hypermrtropia or near sightedness.

2)p=1/f
p=1/-4.5
p=-0.22

nature of lens is concave lens

Answer 2

(1) and (2) The power of lens is negative so, Noopur is suffering from Myopia and lens is concave.
P= 1/f
So, Focal length = 1/P
1/4.5 = 0.22m

(3) Here is a diagram I made.
(4) Often, If any of two parents have myopia, children have chances to have myopia. It can also be caused by injury in eye(s).
:)