Question

16. Find the focal length of a lens of power -2.0D. What type of lens is this

17. A doctor has prescribed a corrective lens of power +1.5D. Find the local length of
the lens. Is the prescribed lens diverging or converging?​

Answer 1

Answer:

-0.5

Explanation:

power of lens = -2.0

power=1/focal lenght

p=1/f

-2.0=1/f

f= 1/-2

f = -0.5m

it is a diverging and concave lens

17) answer : 66.67m

explanation

power of lens = + 1.5D

p=100/f

f =100/1.5

f= 1000/15

f = 66.67

as the focal lenght is postive it is convex lens