Question

An illuminated silt is kept at distance 40cm in front of the convex of focal length 15cm .With the help of a ray diagram find the position of the screen to obtain the image

Answer 1

1/v=1/v-1/u

1/15=1/v+1/40

1/v=1/15-1/40

   =25/600

v=24cm

therefore the position of the screen should be 24cm

Answer 2

Explanation:

According To Len's Formula