Question

In Newton's ring experiment, the phase difference between the light waves reaching the 3rd dark ring from the center of the ring will be​

Answer 1

Explanation:

Newton's rings is a phenomenon in which an interference pattern is created by the reflection of light between two surfaces; a spherical surface and an adjacent touching flat surface. It is named after Isaac Newton, who investigated the effect in his 1704 treatise Opticks. When viewed with monochromatic light, Newton's rings appear as a series of concentric, alternating bright and dark rings centered at the point of contact between the two surfaces. When viewed with white light, it forms a concentric ring pattern of rainbow colors, because the different wavelengths of light interfare at different thicknesses of the air layer between the surfaces.

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