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The lens combination as shown in the figure, consists of two lenses, L₁ and L₂, of the focal lengths +10 cm and -10 cm, respectively. The position of the image formed is :

Asked in Re-NEET 2026 · Combinations and silvered lenses

• (1) 20 cm to the left of the concave lens
• (2) 60 cm to the left of the concave lens
• (3) 30 cm to the right of the concave lens
• (4) 60 cm to the right of the concave lens

Step-by-step solution

Why the other options are wrong

• (1) No single slip gives 20 cm; the concave lens receives a virtual object 12 cm beyond it and 1/v=-1/(10)+1/(12) gives 60 cm.
• (3) No single slip gives 30 cm; 30 cm is the object's distance from L₁, not an image distance.
• (4) The distance is right but the side is wrong: v=-60 cm means the image is on the incoming side, to the left of the concave lens.

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