Question

50. Find the position of final image from 'O' for the
arrangement shown.



(1) -24 cm
(2) -120 cm
(3) 40 cm
(4) -20 cm​

Answer 1

option 4=-20

Explanation:

because from lens formula we have

1/f=1/v-1/u

sothat f=-40,u=-40 because left side of the number line

1/v=1/f+1/u

1/v=-1/40+(-1/40)

1/v=-2/40

1/v=-1/40

v=-20