Refractive Indices of Water And Turpentine Oil Essay

To go back Refractive Indices of Water And Turpentine fossil oil color using a tack mirror, a equi lentiform crystalline crystalline lens systeme (made from a candy of known refractive index) and an adaptable object needleAPPARATUSA gibbous lens, an optical needle, a cream mirror, a clamp stand, a spherometer, a plummet line, metre scale, water system and turpentineoil Theroy allows add dispirited amount of water on a flat, plane aerofoil and place a convex lens oer it. This forms a plano-concave lens of water amid the lower surface of convex lens and plane mirror. Let f 1 and f 2 are the central spaces of water lens and convex lens respectively, accordingly focal continuance of the combination isThe focal length of the plano-concave lens is, (i)From lens system Makers formula,=( R 1 = R and R 2 = for water lens.The refractive index of water is , (ii)(where R is the radius of breaking ball of the concave surfaces of the plano-concave lens). The Radius of curvat ure of the lens, is (iii)PROCEDURE For finding the focal length of convex lens streak the rough focal length of the convex lens. Place the plane mirror with the convex lens placed on it above the naiant base of a clamp stand horizontally as its backsheesh lies vertically above the optical centre of the lens. countersink the needle at a height a little more(prenominal) than the rough focal length of the convex lens. Try to remove the parallax between the eyeshade of the object needle and its image solicit. pit the quad 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 measure the distance of the tip of the needle from the plane mirror. Let it be x 2 . (Use plumb line). 2 (vi) Repeat and record 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. Repeat steps (ii) to (iv) as done above .Repeat the procedure with turpentine oil also. For finding l hear the pitch and least count of scale of the spherometer. Place the spherometer on the dry surface of the convex lens. Turn the screw downwards very softly till the tip of the screw just touches the lens. Read and record the reading. honour 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 fat rotations(n)Final reading of the c.s on the glass slabAdditional C.S div. movedh=n x pitch + m x L.CMean h16206.555.50.5550.577526404600.6Aim is to find the refractive index of a) water, b) coconut oil using a plane mirror, and an equiconvex lens made of glass and an adjustable object needle. The theory behind eloquent lens is based on the properties of one or more perspicuouss to create magnifications within a small amount of space.The focus of a bland lens is controlled by the surface of the facile .Water normally forms a bubble shape when adhered to materials such as glass.This desirable property makes water a very suitable prognosis for the production of liquid lens.Essentially the liquid must be transparent so as to study its effects. To generate a liquid lens , a liquid is sandwiched between two pieces of a clear plastic or a glass. Oil (necessarily transparent) can also be chosen to be intaked as a roving 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 rays.TheoryIn optics, refractive index or index of refraction n of a shopping mall (optical medium) is a dimensionless number that describes how light or any radiation propagates with that medium.It is defined as n = c/vwhere c is the hasten 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 fast 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 go through 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 straighten out stand with base and clamp arrangement, a meter scale etc. operation 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 vertically above the optic centre of the lens. Adjust the needl e at a height a little more than the rough focal length of the convex lens. Bring the tip of the needle, at the vertical drumhead axis of the lens, so that the tip of the needle appears touching the tip of its image. live 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 ). once more measure the distance between tip and upper surface of the plane mirror. Let it be x2 Finding the focal length of the combination channelize 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 morose towards a ancestry such that, the required surface is away from the source the distance is to adjusted that the image is, formed on the side 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/f2Result The observations of the try out is tabulated as followsPrecautions The parallax must be removed tip to tip in good order. The lens and plane mirror should be abstemioused thouroughly. The liquid taken should be essentially transparent.Only few drops of liquid should be taken so that the liquid lens layer is not thickSources of error Liquid 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 simple system of measuring the refractive index of any liquid (transparent) using a convex lens and plane mirror. If we keep the mirr or behind a lens and put an object at the focus point of the lens above it, the image of the object will form at the like 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 effectual 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 calculated subtile the focal length of the combination and that of the convex lens, from which the refractive index of the fluid can easily be estimated.