Geetha observes that a person needs a lens of power -4.5 D for correction of her vision. Few questions came to her mind.

91 views
in Physics
closed

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

+1 vote
by (33.3k points)
selected

1. (i) Myopia

2. (ii) 0.22 m

3. (ii) Concave lens

4. (ii) $\frac1P$

5. (i) Dioptre