Question

The word "KVPY" is written on a board and viewed through different lenses such that the board is at a distance beyond the focal length of the lens. Ignoring magnification effects, consider the following statements.
(I) Image (i) has been viewed from the planar side of a plano-concave lens and image (ii) from the planar side of a plano-convex lens.
(II) Image (i) has been viewed from the concave side of a plano-concave lens and image(ii) from the convex side of a plano-convex lens.
(III) Image(i) has been viewed from the concave side of a plano-concave lens and image (ii) from the planar side of a plano-convex lens.
(IV) Image (i) has been viewed from the planar side of a plano-concave lens and image(ii) from the convex side of a plano-convex lens.
Which of the statements are correct?

A. only (III)
B. only (IV)
C. only (III) and (IV)
D. All four

Answer 1

Hint: In case of lens usually there are various types used. Plano concave lens, Plano convex lens and biconvex lens, biconcave lens. All will serve different purposes. Properties of different lenses are different. In the case of concave lenses they always form virtual images. While convex lenses form both virtual and real images.

Complete answer:
Generally the position and type of the image formed depends upon the position of object, type of lens used and focal length of the lens used.

If we consider a convex lens it can form both virtual and real images whereas a concave lens can only form virtual images. It is to be remembered that when only one lens or when only one mirror is present the virtual image formed is always erected and the real image formed is always inverted.
Virtual images cannot be caught on the screen but can be seen with naked eye and generally formed on the same side of the object. Whereas real images can be caught on the screen and can be seen by naked eye too.

When an object is placed in front of a convex lens away from the center then the image formed will be real and inverted and diminished and will be on the other side of the lens. When the object is placed between the center and the focus then image formed will be real, inverted and enlarged
Now, if we place the object between the pole and the focus then the image formed will be virtual and erected.

In the case of concave lenses, image is always virtual and erect.
First image is erected and the second image is inverted.
It is clearly mentioned in the question that the object is placed away from the focal length. So an image formed by a convex lens will be inverted only.
So the first image should be formed by a concave lens while the second image is formed by a convex lens.

So, the correct answer is “Option D”.

Note:
One might get confused with the question mentioning viewed from the planar side and viewed from convex side or viewed from the concave side. The side from which we are viewing doesn’t matter because the image formed here only depends on the type of lens whether it's concave or convex irrespective of the side which we are viewing from.