A point ofject 'O' lies in front of the lens as shown in figure. Find the final position of image formed by the combined lenses.

Options

A. `10 cm` to the right of the lens C
B. `15 cm` to the right of the lens C
C. `20 cm` to the right of the lens C
D. `30 cm` to the right of the lens C

Answer

D

Explanation

For the lens 'A' `(1)/(v) -(1)/(u) = (1)/(f), v_(A) = 15 cm`
For the lens 'B' `u_(2) = 10 cm`, so `v_(2) = prop`
For the lens `C u_(3) = prop` so `v_(3) = 30 cm`