Question

State two applications of convex lens and concave lens.

Answer 1

Convex lens is a converging lens that means it converges parallel rays passing through it, in it the two lenses are curved outwards. Concave lens on the other hand is a diverging lens which means that it would diverge the rays getting refracted through it, in it at least one lens is converging inwards.

Complete answer:
There numerous applications of convex and concave lenses. Out of the many applications the two important application of convex lens and concave lens are:

Convex lens: It is generally used to correct the eye problem known as farsightedness and near-sightedness. The human eye lens sometimes due to various errors can not focus on the retina properly, so the convex lens as it is converging in nature helps in focusing the light on the retina. The second application of convex lens is in refracting telescopes, the telescopes are required to see images far away which are not visible to the naked eye. The light coming from a distance is converged by the first lens and then again is refracted by the second lens so that we can see the image.

Concave Lens: it is used in lasers, there are various types of scanners, DVD players, medical equipment, etc which require lasers. Concave lens as it is diverging in nature bends or disperse the laser in various directions. Suppose we need to bend a laser then we can use a concave lens to do that as it would diverge the laser in the particular direction. The second use of a concave lens is in flashlight, the light from the flash light is focused in a particular direction and we need the light to spread around the whole area so that one can see. Here, the concave lens would diverge the light coming from the flashlight and disperse it into a wide area.

Final Answer: Convex lens can be used in eyeglasses and in refracting telescopes. Concave lens can be used in bending lasers and in flashlights

Note: Here we need to define the two lenses and mention their effect on light which would be passing through both the lenses. Provide two important applications each, for both lenses. The telescope is one such device that uses both a concave and convex lens.