ICSE Class 10 Answered

Write an introduction as well as conclusion on the topic refraction through a lens for board project file

Asked by vinaygarg3837 | 02 May, 2020, 09:19: PM

Expert Answer

Introduction: -

A lens is formed by a transparent material medium bound by two surfaces, of which oneor both surfaces are spherical.

A lens having both surfaces bulging outwards is called a double convex lens or simply a convex lens. A convex lens is thicker at the middle than at the edges.

The convex lens converges the light rays incident on it to a point.

Hence, a convex lens is also known as a converging lens.

A lens having both surfaces curved inwards is called a double concave lens or simply a concave lens.

A concave lens is thicker at the edges than at the middle.

The concave lens diverges the light rays incident on it.

Hence, a concave lens is also known as a diverging lens.

As both the lenses have two spherical surfaces, they will have two centres of curvatures named C1and C2.

The central point of the lens is known as the optical centre. It is represented as O.

The convex lens converges the rays incident on it after refraction to a point on the principal axis. This point is known as the principal focus of the convex lens.

The rays incident on the concave lens appear to diverge from a pointon the principal axis. This point is known as the principal focus of the concave lens.

Conclusion: -

In conclusion, you can mention the nature of images formed by convex lens for various location of object and concave lens.

Also, with reference to the images formed you can state why particular lens is suitable in any of the instrument like telescopes, microscope etc. Give examples or applications of lens in various instruments.

Answered by Shiwani Sawant | 03 May, 2020, 03:25: PM