Question

Two thin lenses each with a focal length of +10 cm are located 30 cm

Answer 1

Two thin lenses each with a focal length of +10 cm are located 30 cm

Ans. The correct answer is: (C) 27 cm 

Explanation:

Do the math twice. For the first lens. 1/f = 1/do + 1/di … di = + 14 cm (real). So this first ‘pre–image’ is formed 14 cm to the right of the first lens, which means it is 16 cm from the second lens. Now redo the math using this ‘pre–image’ as the object located 16 cm away from the second lens. 1/f = 1/do + 1/di … di = + 26.67 cm.
SO MARK AS BRAINIEST PLEASE.