A thin convex lens of focal length `25 cm` is cut into two pieces `0.5 cm` above the principal axis. The top part is placed at (0.0) and an object placed at `(-50 cm, 0)`. Find the coordinates of the image.

Explanation

In Fig., `AB` is the principal axis of original thin convex lens of `f = 25 cm`. If has been cut into two pieces `0.5 cm` above the principal axis. The top part is placed at (0,0) and object `O` is at `(-50 cm, 0)`.
If there were no cut, the object would have been at a height `0.5 cm` from principal axis `AB`.
As `(1)/(v)-(1)/(u)=(1)/(f)`
`(1)/(v)=(1)/(f)+(1)/(u)=(1)/(25)-(1)/(50)=(1)/(50) :. v = 50 cm`
Magnification, `mu = (v)/(u) = (50)/(-50) = -1`
Thus, the iamge would have been formed at `50 cm` from the pole on right side of lens and `0.5 cm` below the principal axis. Hence, w.r.t. the X - axis passing through the edge of the cut lens, the co-ordinates of the image are `(50 cm, - 1cm)`.