Question

Which lens has a virtual focus?

Answer 1

Hint:The point at which light rays originating from a single spot on the object converge is known as the focus. A beam parallel to the principal axis seems to diverge and then converges after passing through the lens from a place on the principal axis.The focus where the light rays coming from a far object, parallel to each other and to principal axis coverage actually is called real focus and when it diverges but appears to coverage if rays are extended back is called virtual focus. Here, we are going to discuss which lens has a virtual focus.

Complete answer:
The concave lens has a virtual focus or a virtual focus is provided by the concave lens.

There is no more focal point. Therefore, the rays are extended backwards to show the virtual focus.

Concave lens:A concave lens diverges a straight light beam from the source into a reduced, upright virtual image.
-It is capable of producing both real and virtual images.
-Concave lenses have at least one curved interior surface.
-Because it is bent round inwards at the centre and bulges outwards through the corners, causing light to diverge on it, a concave lens is also known as a diverging lens.
-They're commonly used to cure myopia since they distort the perception of distance.

Image creation with a concave lens:
-When an object is positioned at infinity, a virtual image is formed at the focus. The image is a fraction of the size of the actual thing.
-When an object is positioned at a finite distance from the convex lens, a virtual image is generated between the pole and the focus. The image is a fraction of the size of the object.

Therefore, the concave lens has virtual focus.

Note:Concave lenses bend inward, causing light to spread out and giving the observer a smaller image. Despite the fact that they are less useful than convex lenses, they are nonetheless used in eyeglasses and contacts, flashlights, peepholes, binoculars, telescopes, and photography.