Question

A point object $O$ is placed at a distance of $0.3m$ from a convex lens (focal length $0.2m)$ cut into two halves each of which is displaced by $0.0005m$ as shown in the figure.
If this arrangement will generate more than one image, then what will be the total number of images?

• A. $2$
• B. $4$
• C. $6$
• D. $5$

Answer 1

Answer: (A)

$2$

For each part of the lens, refraction would happen as shown in the figure.

For each portion of the lens, it seems as if the object is not on the principle axis, but at some distance from it. Thus the upper half forms an image above the center line. Similarly the lower half forms one below the center line.