tell me why there are circular fringes in newtons rings

Newton's rings are a phenomenon caused by the interference of light. Here's a step-by-step explanation:

1. Light Interference: Newton's rings are caused by the interference of light, which is a phenomenon that occurs when two light waves superpose to form a resultant wave of greater, lower, or the same amplitude.

2. Reflection and Refraction: When a beam of light hits a glass plate, some of it is reflected off the surface, and some of it is refracted through the glass. The refracted light can then be reflected off a second surface (like another glass plate or the back of the first plate) and recombine with the directly reflected light.

3. Path Difference: The recombined light waves have traveled different distances (the directly reflected wave and the wave that was refracted then reflected). This path difference can cause the waves to interfere constructively (forming bright fringes) or destructively (forming dark fringes).

4. Circular Fringes: The pattern of these fringes forms concentric circles around the point of contact between the two surfaces. This is because the path difference between the two waves changes radially from the point of contact. At the point of contact, the path difference is zero, so a bright fringe is observed. As you move away from this point, the path difference increases, leading to alternating bright and dark fringes.

5. Dependence on Wavelength: The exact pattern of Newton's rings depends on the wavelength of the light used. Different colors of light will produce rings of different sizes because the condition for constructive and destructive interference depends on the wavelength of the light.

So, the circular fringes in Newton's rings are a result of the interference of light caused by the difference in the paths traveled by the light waves.

Newton's rings are a phenomenon caused by the interference of light. Here's a step-by-step explanation:

1. Light Interference: Newton's rings are a result of the interference of light. Interference is a phenomenon in which two light waves superpose to form a resultant wave of greater or lower amplitude.

2. Reflection and Refraction: When a beam of light hits a lens resting on a flat surface, it splits into a reflected beam and a refracted beam. The reflected beam comes from the light reflecting off the top surface of the lens. The refracted beam comes from the light that passes through the lens, reflects off the flat surface, and then travels back up through the lens.

3. Path Difference: The reflected and refracted beams have traveled different distances. This difference in path length causes the light waves to be out of phase with each other when they meet again.

4. Constructive and Destructive Interference: When the path difference between the two beams is a whole number of wavelengths, the waves are in phase and constructive interference occurs, resulting in a bright fringe. When the path difference is a half-integer multiple of the wavelength, the waves are out of phase and destructive interference occurs, resulting in a dark fringe.

5. Circular Fringes: The pattern of these fringes forms concentric circles around the point of contact between the lens and the flat surface. This is because the path difference between the two beams changes radially from the point of contact. The path difference is zero at the point of contact (resulting in a dark spot), and increases with the radial distance from this point. This results in alternating bright and dark circular fringes, known as Newton's rings.