Question

An object of 1 cm in length is placed at a distance of twice of focal length from a convex lens. the size of the image formed is?

Answer 1

Answer:

Let focal length be f, u=2f

1/v-1/u=1/f

1/v=1/f+1/u

1/v=1/f+1/2f=3/2f

v=2f/3

size of the image/size of the object=v/u

size of the image/1=v/u=(2f/3)/(2f)=1/3

size of the image =1/3 cm