Refractive Indices of Water And Turpentine Oil Essay

To find Refractive Indices of Water And oil of turpentine Oil utilise a insipid mirror, a equiconvex electron genus Lens (made from a candy of known refractive mightiness) and an adjustable object chevvy applianceA convex crystalline crystalline crystalline electron lens, an ocular prick, a plane mirror, a secure stick out, a spherometer, a plumb line, metre racing shell, water and turpentineoil Theroy Lets add small amount of water on a flat, plane lift and post a convex lens all over it. This forms a plano-concave lens of water between the lower break through of convex lens and plane mirror. Let f 1 and f 2 are the key lengths of water lens and convex lens respectively, then focal length of the cabal isThe focal length of the plano-concave lens is, (i)From Lens Makers formula,=( R 1 = R and R 2 = for water lens.The refractive proponent of water is , (ii)(where R is the universal gas constant of curve ball of the concave come ons of the plano-concave le ns). The Radius of bender of the lens, is(iii)PROCEDURE For finding the focal length of convex lens Measure the jittery focal length of the convex lens. mystify the plane mirror with the convex lens determined on it in a higher place the horizontal base of a clamp stand horizontally as its get onto lies straightly above the optical tenderness of the lens. Adjust the needle at a height a littler more than the rough focal length of the convex lens. Try to omit the parallax between the lean of the object needle and its image tip. no.e the outmatch of the tip of the needle from the centre of the upper surface of the lens. Let it be x 1. (Use plumb line). Remove the convex lens and whole step the remoteness of the tip of the needle from the plane mirror. Let it be x 2 . (Use plumb line). 2 (vi) Repeat and study all the observations. For finding the focal length of the plano-concave lens Pour few drops of water over the plane mirror and place the convex lens over it. Repea t locomote (ii) to (iv) as done above.Repeat the procedure with turpentine oil also. For finding lDetermine the pitch and least count of scale of the spherometer. Place the spherometer on the dried surface of the convex lens. Turn the screw downwards genuinely gently till the tip of the screw just touches the lens. Read and record the reading. Keep the spherometers legs on the base of a paper and adjusting the central screw, find the pricks A, B and C of the three legs of the spherometer. Join the centres of the three pricks and measure the lengths with the half-metre scale. Note the values of AB, BC and ACConclusionPitch of the spherometer= 1 cmLeast count of the spherometer = 0.01 cmDistance between the legs AB = 3 cm BC = 3 cmCA = 3 cmS.NoInitial reading of the C.S. on the convex lens(a)No. of complete rotations(n)Final reading of the c.s on the glass slabAdditional C.S div. locomoteh=n x pitch + m x L.C pissed h16206.555.50.5550.577526404600.6Aim is to find the refractive in dicator of a) water, b) coconut meat oil using a plane mirror, and an equiconvex lens made of glass and an adjustable object needle. The theory tail end naiant lens is found on the properties of one or more liquids to create magnifications within a small amount of space.The focus of a liquid lens is controlled by the surface of the liquid .Water normally forms a bubble shape when adhered to materials much(prenominal) as glass.This desirable spot arrives water a very equal candidate for the production of liquid lens.Essentially the liquid must be out-and-out(a) so as to study its effects. To generate a liquid lens , a liquid is sandwiched between two pieces of a clear flexible or a glass. Oil (necessarily transparent) can also be elect to be used as a fluid in a liquid lens system. The surface profiles of the liquid determines the focal length of liquid lens system and how the liquid lens focusses light emits.TheoryIn optics, refractive mightiness or index of refraction n of a substance (optical medium) is a dimensionless number that describes how light or any ray propagates through that medium.It is defined as n = c/vwhere c is the speed of light in vaccum and v is the speed of light in a substance. Eg n of water is 1.33, which means, light travels 1.33 times as unbendable in vaccum as it does in water. The historically first occurance of refractive index was in Snells law of refraction. ie are the angles of incidence of the ray crossing the interface between 2 medias with refractive indeces n_1 and n_2. In this project, we shall make use of the property of liquid lens to find the refractive index of water and coconut oil.RequirementsA convex lens, plane mirror, water, coconut oil, an optical needle, an iron stand with base and clamp arrangement, a meter scale etc. Procedure Finding the focal length of convex lens- Place the plane mirror with the convex lens placed on it above the horizontal base of a clamp stand horizontally as its tip lies v ertically above the optic centre of the lens. Adjust the needle at a height a little more than the rough focal length of the convex lens. Bring the tip of the needle, at the vertical principal axis of the lens, so that the tip of the needle appears touching the tip of its image. Move the needle up and down to remove the parallax between tips of needle and its image. Measure the distance between tip of the needle and upper surface of the lens by using a meter scale. Let it be (x1 ). Again measure the distance between tip and upper surface of the plane mirror. Let it be x2 Finding the focal length of the combination Take a few drops of the given transparent liquid and place it on the surface of plane mirror. The convex lens is placed over it as before. (A plano concave lens is formed between plane mirror and convex lens). Repeat the steps (ii) to (v) Record the observations. To find the radius of curvature of the liquid lens. (R of convex lens surface in contact). The convex lens is t urned towards a source such that, the required surface is onward from the source the distance is to adjusted that the image is, formed on the look of the source. The distance d between the source and the lens is measured.The radius of curvature R of the lens is given byFinally the refractive index of liquid lens is given by.n = 1+ R/f2 contribute The observations of the experiment is tabulated as followsPrecautions The parallax must be removed tip to tip properly. The lens and plane mirror should be cleaned thouroughly. The liquid taken should be basically transparent.Only few drops of liquid should be taken so that the liquid lens layer is non thickSources of error runny may not be quite transparent The parallax any not be fully removed The needle may not be properly horizontalThe distance x1 and x2 may not be essentially cleanThe experiment described in this project is an effective and unreserved method of measuring the refractive index of any liquid (transparent) using a c onvex lens and plane mirror. If we keep the mirror behind a lens and put an object at the focus localize of the lens above it, the image of the object allow for form at the same focus point where the object is. If it is an extended object, its image will be inverted and the size of image is same as that of the object. This property has enabled the efficient use of liquid lens to find the refractive index of a fluid by this method. If a liquid is sandwiched between the lens and the mirror, the focal length of liquid lens can be measured knowing the focal length of the combination and that of the convex lens, from which the refractive index of the fluid can easily be estimated.