Geetha observes that a person needs a lens of power -4.5 D for correction of her vision. Few questions came to her mind. Give answers to the below questions:
1. What kind of defect in vision is she suffering from?
(i) Myopia
(ii) Hypermetropia
2. What is the focal length of the corrective lens?
(i) 0.9 m
(ii) 0.22 m
Q 3. What is the nature of the corrective lens?
(i) Convex lens
(ii) Concave lens
4. What is the formula for finding the focal length of the lens?
(i) \(\frac{1}{P^2}\)
(ii) \(\frac1P\)
(iii) P
5. What is the unit for measuring the power of the lens?
(i) Dioptre
(ii) Millimeter
