Waves & optics Newton Rings By GurwinderSingh 1043/12 To j.p.sir physics Waves & optics Newton Rings By GurwinderSingh 1043/12 To j.p.sir

NEWTON’S OBSERVATIONS In 1717,Isaac Newton performed Ist time this experiment in LAB by using a monochromatic light. He observe that co-centric rings are formed of a specific colour.but when he perform same exp. With white light he observe that rings a co-centric but rings show rainbow color pattern[VIBGYOR].

REASON OF RAINBOW PATTERN Main cause of rainbow pattern is lights of different wavelength interfere at different thicknesses of air layer between two surfaces…………

RINGS FORMED BY USING REFLECTD SYSTEM

RINGS FORMED BY USING REFLECTING SYSTEM S is a source of light.l is a convex lens use to rendered parallel the rays..G is a mirror working as a obstacle placed at 45 degree to path of ray as a result ray reflect and incident normally on plano-convex lens placed on optically plane glass plate.. “the reflection of beam from lower surface of lens and upper surface of glass plate produce coherent rays & gives us interference patteren”

RESULTANT RINGS

INTERFERENCE DIAGRAM

RINGS PRODUCE BY USING TRANSMITTED SYSTEM

RINGS PRODUCE BY TRANSMITTED SYSTEM In this system one ray suffer no reflection but 2nd one suffer double reflection 1st at lower surface of lens another at upper surface of flat glass plate……….two rays shown in figure are differ only by path difference but their phase is same

BASIC DIFFERENCE B\W REFLECTED AND TRASNMITTED SYSTEM Both are complementary to each other bright fringe in reflected system become dark in transmitted system and vice-versa…….….but central fringe is bright……………

APLLICATIONS OF NEWTON RINGS 1.used to measure wavelngth;;;;using formula

APPLICATIONS OF NEWTON RINGS 2.used to measure refractive index of material;;;; using formula

THNKZ 2 OL