Question

Which of the following always form virtual images?
(A) Concave mirror and convex lens.
(B) Convex mirror and concave lens.
(C) Concave mirror and convex lens.
(D) Concave mirror and concave lens

Answer 1

Hint : Virtual images are images that cannot be formed on a screen. For mirrors, they are formed behind the mirror, and for lenses, they are formed on the same side of the lens where the object is placed.

Complete step by step answer
Generally, virtual images are images that are unreal hence cannot be formed on a screen. For mirrors, they are formed behind the mirror (as in inside the mirror), and for lenses they are formed on the same side of the lens where the object is placed.
To know the correct combination which always produces a virtual image, we shall investigate the properties of the two types of lens and mirror.
Concave mirror – this mirror almost always produces a real image. It can only produce a virtual image when the object is placed between the focal point and the lens.
Concave lens – this is a lens which has an image that is always virtual. They are also called diverging lenses.
Convex mirror – this is a lens which also produces virtual images at all times or position of an object. It is also called a diverging mirror.
Convex lens – this is a lens which almost always produces real images which can be projected on a screen.
Hence, the combination of the lens and mirror which are always virtual are concave lens and convex mirror.
Hence, the correct option is B.

Note
For clarity, images are considered real when their light rays coming from the object actually converge at a point and thus can form an image which can be an object to the eye. But virtual images are not formed by converging rays, rather rays which appear to diverge from a point. Hence, real light rays cannot be incident on it and be a real object to the eye,