Question

A four times enlarged virtual image of an object ,placed at a distance of 15 cm from a lens ,is formed.Find the distance of image from the lens and focal lenght of the lens.​

Answer 1

Answer:

focal length =12cm&v=60cm

Explanation:m=v/u as v=m×u=-15×-4=60cm

1/v-1/u=1/f ,1/60-1/-15=1/60+1/15=1/60+1×4/15×4=1/60+4/60

=1/12,therefore,f=12cm

hope it helps uuu