Question

The graph correctly representing the variation of image distance ’v’ for a convex lens of focal length ’f’ versus object distance ’u’ is ______.
Fill in the blank with the correct answer from the options given below

• A.
• B.
• C.
• D.

Answer 1

Answer: (C)

Answer 2

For a convex lens, the relationship between object distance u, image distance v, and the focal length $f$ is given by the lens formula:
$\frac{1}{f} = \frac{1}{v} + \frac{1}{u}$
This equation indicates that as the object distance approaches infinity, the image distance approaches the focal length from the positive side. Similarly, as the object moves closer to the lens, the image distance changes rapidly. Therefore, the graph is a curve that approaches the focal length but never touches it.