Question

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

Answer 1

+1.5 means it is convex lens
and
focal length is
p = 1/f
15/10 = 1/f
f = 2/3 or 0.6m

Answer 2

We know,Power = 100/for, 1.5 = 100/for, f = 100/1.5 = 66.6

The focal length of the lens = 66.6 cm

The prescribed lens is converging.m=1 indicates that the image is of the same size as the object.

Thus, the magnification of +1 produced by a plane mirror means the image formed in a plane mirror is virtual, erect and of the same size as the object.