AIM :- To Determine The Wavelength Of Light By Newtons Ring Metho

Newtons RingsTravelling Mi!ros!o"eT#$OR% :-The formation of Newtons Ring is due to the interference of light waves reflected from the upper & lower surface of the air film enclosed between the lens & plane glass plate . The thickness of the air film at the point of contact is zero & increases as we move from the point of contact towards the periphery of the lens . The thickness of the air film will be uniform for all points lying on a circle with centre at the point of contact . Thus using reflected light, the central point will be dark surrounded by the bright circles separated by dark rings . f !n be the diameter of the nth bright ring & !m be the diameter of the mth bright ring, R be the radius of the curvature of the surface of the lens in contact with glass plate, then the wavelength " of the light is given by = (Dm2~ Dn2) {4R(m ~ n) }O&servations :- Ta&le e :-Determination ofleast !o'nt of travelling mi!ros!o"e #crew $itch%p&%in cm&No. of circular scale divisions%n& l. c. 'p / n%cm.& Ta&le & :-Meas'rement of the Diameter of the rings :-No.ofRings(icroscope ReadingDm =(x ~ y)in cm.Dm2 incm2)eft %x& Right %y&(ainscalereading%(#R&%in cm&*ircularscalereading%*#R&TotalReading(#R +%*#R,)*& %in cm&(ainscalereading%(#R&%in cm&*ircularscalereading%*#R&TotalReading(#R +%*#R,)*& %in cm& (al!'lation :- )er!entage $rror :-Dis!'ssions :-