CAT NO: DIDACTICELECTROMETER0032
NEWTON S RINGS.
NEWTON S RINGS TRAINING PROGRAM • determining the wavelength of sodium light • determining the index of refraction of a liquid by using Newton’s ring apparatus • determining the radius of curvature of plano-convex lenses with the test of Newton’s rings • determining the thickness of a thin paper sheet IMPORTANT CHARACTERISTICS • all the components, including sodium-vapour lamp, microscope, power supply unit and optical plates, are assembled in a unique unit • optical plates of glass mounted at 45° • simple collimation • quick adjustment, good quality, well defi ned separate fringes • matt black-painted housing for set of Newton’s rings COMPONENTS • Newton’s ring apparatus • Spherometer • Plano-convex lenses with fl at pane of glass Newton’s ring apparatus This apparatus is used to determine the wavelength of sodium light. A fi gure consisting of a series of alternating dark and clear concentric rings is displayed : these rings are thinner and thinner as they go from centre to periphery. All the components, including sodium-vapour lamp, microscope, power supply unit and optical plates, are assembled in a compact unit. The system is equipped with plano-convex lenses of wide focal length, and with circular fl at pane of glass. • Dimensions: 390 x 480 x 170 mm • Micrometer: 0.01 mm • Eyepiece: 10x - Lens: 3x • Weight: approximately 12.6 kg Spherometer This spherometer enables to measure the radius of curvature of plano-convex lenses. It has two disks and 3 feet. Ruler and two disks are of brass. Diameter of head disk of micrometer: 40 mm. The lower disk that is wider has a diameter of 60 mm. This instrument is equipped with a pane of glass. Range of 10-0-10 mm. IMPORTANT CHARACTERISTICS • Microscope can work in both horizontal and vertical directions • Newton’s ring apparatus with pane of glass at 45° COMPONENTS • Newton’s ring unit with reflector • sodium light source • bridge microscope • wood block • spherometer • plano-convex lenses with fl at pane of glass Newton’s ring apparatus with reflector Il consists of a matt black framework with a pane of glass mounted at 45° to refl ect the light downwards on a planoconvex lens of wide focal length laying on a fl at pane of glass. The equipment includes plano-convex lenses. Sodiun light source Sodium light source with circular opening having a diameter of 25 mm, and with a transformer. Bulb socket of brass for lamp of 2 A 220 Vac. This source is fi xed on a rod installed on a base. • Input voltage: 470 V • operating voltage: 220 V, 50 Hz • light source: 300 x 85 mm (diameter) Bridge microscope This type of microscope is used in the tests on Newton’s rings and it can work in both horizontal and vertical directions. The microscope with pinion alignment is positioned vertically and it can be fi xed in vertical or horizontal position. • Eyepiece: 10x - Lens: 3x • Scale length: 110 mm