Behind A Thin Converging Lens Having Both The Surfaces Of The Same Radius 1 Cm, A Plane Mirror Has Been Placed. The Image Of An Object At A Distance Of 40 Cm From The Lens Is Formed At The Same Position. What Is The Refractive Index Of The Lens?                                                        

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Behind a thin converging lens having both the surfaces of the same radius 1 cm, a plane mirror has been placed. The image of an object at a distance of 40 cm from the lens is formed at the same position. What is the refractive index of the lens?



Correct option is



O” act as the focal point.





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