Question

A thin converging lens is found to form an image of a distant building 24 cm from the lens. If an insect is now placed 16 cm from this lens, how far FROM THE INSECT will its image be formed?

A) 64 cm

B) 72 cm

C) 32 cm

D) 96 cm

E) 48 cm

Answer 1

since the rays from the building may be considered parallel, we have f = 24. So, to find the distance of the insect's image (from the lens),

1/16 + 1/x = 1/24

Use that to arrive at your final answer.