Question

Which type of lens always forms a virtual image?

Answer 1

Hint: The concave lens is the diverging lens while the convex lens is the converging lens. Properties of the image formed by concave are exactly opposite to the properties of the image formed by convex. The image formed by convex is real and downward. The virtual image is formed by extending the refracted lens from the lens.

Complete answer:
A concave lens is a diverging lens. In the concave lens, there are three types of rays of light. The first type of ray is the ray of light which is parallel to the principal axis after refraction appears to be coming from the focus.
The second type of ray is the ray of light going towards the optical center of a concave lens that goes straight through without being deviated.
The third type of ray is the ray of light going towards the focus after refraction becomes parallel to the principal axis.

The ray diagram given below contains only two types of rays.

Place a pencil placed in front of a concave lens. First, the ray emerges from the top of the pencil, and on the lens, it refracted and after refraction, it extended towards the backward direction and it appears to come towards a focus that is ${{F}_{2}}$. Now the ray going toward the optical center is going straight without being deviated.

The point where the extended ray and second ray meets, there an image of a pencil is formed. The properties of the image are virtual and upright.
The concave type of lens always forms a virtual image.

Note:
The image formed by a concave lens is virtual, upright, and diminished. The image is formed between the object and lens. Now if you change the position of an object then you get the image having similar property. So no matter where the object is placed, the property of the image will always be the same i.e. virtual, upright and diminished and it formed between object and lens. But a convex lens has many different cases based on a variety of positions of the object.