Number of images formed by two concave lens, one displaced from optical axis

AI Thread Summary
A biconvex lens cut into two halves is discussed regarding the number of images formed when a point object is placed to the left. The initial analysis suggests that two images will form due to the coinciding focal lengths of the upper and lower parts. However, the textbook states that three images will be formed, prompting confusion. The discussion highlights that the different positions of the lens halves lead to images being formed at slightly different distances. Clarification is also provided regarding a potential misidentification of the lens type.
Sumedh
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Homework Statement


A biconvex symmetrical lens is cut in two halves and placed as shown in figure.
if a point object is placed in the left how many images will be formed
options - (a) Two images
(b) Three images


Homework Equations





The Attempt at a Solution



As I have used the lens makers formula the focal length of upper part and lower part is same
so they will form images that coincides and hence one image will be formed and the other image will be formed by the middle (thick overlapping part)
so finally 2 images will be formed.
but the answer that is given in my book is (b)Three images will be formed.

I will be very thankful even if hints are provided.
 

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Sumedh said:

Homework Statement


A biconvex symmetrical lens is cut in two halves and placed as shown in figure.
if a point object is placed in the left how many images will be formed
options - (a) Two images
(b) Three images

Homework Equations


The Attempt at a Solution



As I have used the lens makers formula the focal length of upper part and lower part is same
so they will form images that coincides and hence one image will be formed and the other image will be formed by the middle (thick overlapping part)
so finally 2 images will be formed.
but the answer that is given in my book is (b)Three images will be formed.

I will be very thankful even if hints are provided.

While the lens-makers formula shows the upper part and lower part have the same focal length, the position of each is slightly different.
Unless the object is placed at "infinity", the image formed by each part will be at slightly different distances from the object.

EDIT: Note you have drawn a bi-concave lens, not a bi-convex lens! Perhaps you just used the wrong name?
 
PeterO said:
Perhaps you just used the wrong name?
I was sorry for that.

Thank you very much.
 
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