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Amith2006
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# A convex lens placed between an object and screen forms a sharp image of the object on screen. A glass slab of refractive index n is inserted between object and lens. In order to obtain the sharp image on the screen again the lens has to be displaced by a distance x. What is the thickness of the slab?
I solved it in the following way:
Let t be the thickness of the slab.
Shift in position of image due to the insertion of glass slab = [t(n-1)]n
i.e. x = [t(n-1)]n
t = (nx)/(n – 1)
But the answer given in my book is n/x.
I solved it in the following way:
Let t be the thickness of the slab.
Shift in position of image due to the insertion of glass slab = [t(n-1)]n
i.e. x = [t(n-1)]n
t = (nx)/(n – 1)
But the answer given in my book is n/x.