# Why is the plano convex lens of large radius of curvature used in Newton’s rings experiment?

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At the point of contact of lens and the plate thickness is zero, so optical path difference becomes only λ/2 which is condition for destructive interference. … iv)When a planoconvex lens of large radius of curvature is placed on a flat glass plate, a thin film of air is trapped between lens and plate.

## Why we use plano-convex lens in Newton’s ring?

Alternate dark and bright rings formed due to presence of air film when plano-convex lens is placed on glass plate are called Newton’s rings. When a plano-convex surface is placed on a glass plate, an air film of gradually increasing thickness is formed.

## Why should we use convex lens of large radius of curvature?

A convex lens with large radius of curvature has less curved surfaces and hence the air film b/w less curved surfaces and a plane surface will be appropriately thin to make the interference effect visible..

## What type of plano-convex lens is preferred for Newton’s rings formation?

5: Newton’s rings seen in two plano-convex lenses with their flat surfaces in contact. One surface is slightly convex, creating the rings. In white light, the rings are rainbow-colored, because the different wavelengths of each color interfere at different locations.

## What will be effect on Newton’s ring if a plano-convex lens of small radius of curvature is used?

The diameter of the rings will decrease because the diameter of the rings is inversely proportional to the refractive index. Q. What will happen if we use a lens of small radius of curvature? … Then the rings will be of smaller diameter and there is chance of error while taking the readings.

## What is radius of curvature in Newton’s ring experiment?

The lens in a Newton’s rings experiment has diameter 20 mm and radius of curvature R = 5.0 m.

## What is plano-convex lens?

Plano-convex lenses are positive focal length elements that have one spherical surface and one flat surface. These lenses are designed for infinite conjugate (parallel light) use or simple imaging in non-critical applications. These optic lenses are ideal for all-purpose focusing elements.