To find Echoing Indices of Water And Essay

To find Refractive Directories of Water And Turpentine Oil by using a plane mirror, a equiconvex lens (made from some known refractive index) and an adjustable object needle EQUIPMENT:

A convex lens, an optical needle, a airplane mirror, a clamp stand, a spherometer, a plumb line, metre scale, drinking water and turpentine oil Theroy:

Let's add small amount of normal water on a flat, plane surface area and place a convex lens over it. This kind of forms a plano-concave contact lens of water between the reduced surface of convex lens and plane mirror. Allow f you and f 2 are definitely the focal extent of drinking water lens and convex zoom lens respectively, then simply focal entire combination is definitely:

The focal length of the plano-concave lens can be,  …(i)

Via Lens Maker's formula,


R you = Ur and 3rd there�s r 2 = for normal water lens.

The refractive index of normal water is, …(ii)

(where ‘R' is the radius of curvature of the cavite surfaces from the plano-concave lens). The Radius of curvity of the zoom lens, is



•  For finding the key length of convex lens:

•  Measure the tough focal entire convex zoom lens.

•� You can put plane looking glass with the convex lens added to it over a horizontal bottom of a grip stand flat as its idea lies vertically above the optic centre from the lens. Adapt the hook at a height a tad bit more than the rough focal length of the convex lens. •  Try to get rid of the parallax between the idea of the target needle and its particular image hint. •� Take note the distance in the tip with the needle from the centre with the upper surface of the zoom lens. Let it be x 1 . (Use straight line). •� Remove the convex lens and measure the range of the suggestion of the needle from the plane mirror. Allow it be by 2 . (Use plumb line). 2 (vi) Repeat and record every one of the observations.

•  For finding the focal length of the plano-concave lens: Put few drops of normal water over the planes mirror and place the convex lens about this. Repeat measures (ii) to (iv) while done above. Repeat the process with turpentine oil likewise. •� For locating ‘l':

Determine the pitch and least count of scale in the spherometer. Put the spherometer around the dried surface area of the convex lens. Convert the screw downwards extremely gently till the tip from the screw only touches the lens. Browse and record the studying. Keep the spherometer's legs on the base of any paper and adjusting the central mess, find the pricks A, B and C of the three lower limbs of the spherometer. Join the centres of the three pricks and gauge the lengths while using half-metre level. Note the values of AB, BC and AIR CONDITIONING UNIT


Presentation of the spherometer= 1 cm

Least count number of the spherometer = 0. 01 centimeter

Distance between legs:

•� AB sama dengan 3 centimeter

•� BC = 3 cm

FLORIDA = 3 cm

T. No

Initial reading of the C. S i9000. on the convex lens


No . of complete shifts


Final reading with the c. s on the glass slab

Further C. S i9000 div. transferred

h=n x pitch + m x L. C

Mean " h”




6. 5

55. your five

0. 555

0. 5775






0. 6


Aim is always to find the refractive index of a) water, b) coconut olive oil using a airplane mirror, and an equiconvex lens made of glass and an adjustable subject needle. The idea behind liquefied lens will be based upon the real estate of one or maybe more liquids to create magnifications in a small amount of space. The focus of a liquid lens is regulated by the surface with the liquid. Water normally varieties a bubble shape when ever adhered to components such as cup. This attractive property makes water an extremely suitable prospect for the availability of liquefied lens. Essentially the liquid must be transparent in order to study it is effects. To have a liquid zoom lens, a the liquid is placed between two pieces of an obvious plastic or a glass. Petrol (necessarily transparent) can also be decided to be used like a fluid within a liquid contact lens system. The surface profiles of the liquid can determine the key length of liquid lens system and how the liquid contact lens focusses mild rays. Theory:

In optics, refractive index or index of refraction ‘n' of a substance (optical medium) can be described as dimensionless amount that describes how light...