Look at the ray diagram shown ,what will be th focal length of th e`1^(st)`and the `2^(nd)`lens,if the incident light ray passes without any deviation?

Answer

C

Explanation

From figure `1^(st)` behave as diverging and `2^(nd)` behave converging
In `1st` incident ray appear to pass at 5 cm distance point and after refraction it becomes parallel to principal axis i.e. the focal length = -5cm and for second f=5 cm