Question

a concave lens of focal length 8 cm from a real image of the same size as the object what is the distance between the object and the image​

Answer 1

concave lens never makes a real image. there are two cases of concave lenses

1. when the object is kept at optical centre then the image formed is between the optical centre and the focus which is virtual and erect and diminished.
2. when the object is kept at infinity from the concave lens then the image formed is at focus and it is a virtual and erect image and highly diminished.

thus in both cases the image formed is virtual so in a concave lens no real images formed so in above question the image formed is real which is not possible so that answer is not possible.

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