Refractive indices of water and turpentine

To find Refractive Directories of Drinking water And Turpentine Oil by using a plane mirror, a equiconvex lens (made from some known echoing index) and an adjustable target needle

DEVICE:

A convex zoom lens, an optic needle, a plane reflect, a grip stand, a spherometer, a plumb collection, metre range, water and turpentine

essential oil Theroy:

Let’s put small amount of water on a level, plane surface area and place a convex contact lens over it. This kind of forms a plano-concave lens of drinking water between the decrease surface of convex lens and planes mirror.

Permit f 1 and f 2 would be the focal measures of drinking water lens and convex contact lens respectively, then focal length of the combination is usually:

The focal length of the plano-concave lens is usually, ¦(i)

From Zoom lens Maker’s solution

=( R one particular = L and Ur 2 = for water lens.

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

(where ‘R’ is the radius of curvature of the curvy surfaces in the plano-concave lens). The Radius of curvity of the lens, is¦(iii)

TREATMENT

¢ For finding the focal duration of convex contact lens:

¢ Measure the tough focal length of the convex contact lens.

¢ Place the aircraft mirror together with the convex zoom lens placed on this above the horizontally base of a clamp stand horizontally as its tip is placed vertically over a optical middle of the contact lens. Adjust the needle by a elevation a little more compared to the rough focal length of the convex lens.

¢ Try to remove the parallax between the suggestion of the subject needle and its image suggestion.

¢ Note the space of the tip of the filling device from the middle of the upper surface with the lens. Let it be times 1 . (Use plumb line).

¢ Remove the convex lens and measure the distance of the tip of the hook from the airplane mirror. Allow it to be times 2 . (Use plumb line). 2 (vi) Repeat and record all the observations.

¢ For locating the central length of the plano-concave lens: Put few drops of normal water over the airplane mirror make the convex lens about this. Repeat measures (ii) to (iv) while done previously mentioned. Repeat the method with turpentine oil also.

¢ For finding ‘l’:

Determine the pitch and least count of level of the spherometer. Place the spherometer on the dried surface from the convex contact lens. Turn the screw down very carefully till the end of the mess just touches the contact lens. Read and record the reading. Maintain the spherometer’s hip and legs on the basic of a paper and altering the central screw, locate the pricks A, M and C of the three legs from the spherometer. Sign up for the centres of the three pricks and measure the measures with the half-metre scale. Note the ideals of AB, BC and AC

Conclusion

Pitch in the spherometer= 1 cm

Least count number of the spherometer = zero. 01 centimeter

Length between the lower limbs:

¢ AB sama dengan 3 cm

¢ BC = 3 centimeter

FLORIDA = three or more cm

S. Not any

Primary reading with the C. H. on the convex lens

(a)

No . of complete rotations

(n)

Final examining of the c. s within the glass slab

Added C. S i9000 div. shifted

h=n x frequency + m x D. C

Mean “h

you

sixty two

zero

6. 5

55. 5

zero. 555

0. 5775

two

sixty four

0

some

60

0. 6

Aim is to locate the echoing index of a) water, b) coconut oil using a plane mirror, and an equiconvex lens made of goblet and an arm object hook. The theory in back of liquid lens is based on the properties of 1 or more fluids to create magnifications within a tiny amount of space. Primary of a the liquid lens is controlled by the surface area of the liquefied. Water normally forms a bubble shape when honored materials such as glass. This kind of desirable property makes normal water a very appropriate candidate for the production of liquid zoom lens. Essentially the water must be clear so as to study its effects. To generate a liquid lens, a liquid is sandwiched between two components of a clear plastic-type or a glass. Oil (necessarily transparent) may also be chosen to be taken as a fluid in a water lens program. The surface profiles of the the liquid determines the focal period of liquid lens system and just how the liquefied lens focusses light light.

Theory:

In optics, refractive index or perhaps index of refraction ‘n’ of a compound (optical medium) is a dimensionless number that describes how light or any radiation propagates through that medium. It really is defined as n = c/v

where’ c’ is the speed of light in vaccum and ‘v’ is the exceedingly fast in a substance. Eg: ‘n’ of normal water is 1 ) 33, meaning, light journeys 1 . 33 times because fast in vaccum since it does in water. The historically 1st occurance of refractive index was in Snell’s law of refraction. for example are the angles of incidence of the beam crossing the interface among 2 medias with echoing indeces n_1 and n_2. In this task, we shall utilize the property of liquid zoom lens to find the refractive index of water and coconut oil.

Requirements

A convex lens, plane mirror, water, coconut oil, a great optical needle, an straightener stand with base and clamp set up, a colocar scale etc¦. Procedure:

¢ Finding the focal period of convex zoom lens: –

¢ Put the plane looking glass with the convex lens positioned on it over a horizontal bottom of a clamp stand flat as its suggestion lies vertically above the optic centre from the lens. Adjust the needle at a height more than the rough focal entire convex lens.

¢ Bring the idea of the needle, at the vertical principal axis of the zoom lens, so that the hint of the needle appears touching the tip of its photo.

¢ Move the needle up and down to remove the parallax between tips of needle and its image.

¢ Measure the distance between tip in the needle and upper surface area of the zoom lens by using a meter scale. Allow it to be (x1 ).

¢ Once again measure the range between hint and uppr surface from the plane mirror. Let it end up being x2

¢ Locating the focal length of the combination:

¢ Have a few drops of the provided transparent water and place it on the surface area of plane mirror. The convex lens is placed over it as before. (A optica concave contact lens is formed between plane looking glass and convex lens).

¢ Do it again the steps (ii) to (v)

¢ Record the observations.

¢ To obtain the radius of curvature in the liquid zoom lens. (R of convex lens surface in contact). The convex zoom lens is switched towards a source in a way that, the required area is away from source the length is to adjusted that the picture is, created on the side in the source. The space ‘d’ involving the source as well as the lens is usually measured.

The radius of curvature ‘R’ of the zoom lens is given simply by

Finally the refractive index of liquid lens has by.

n = 1+ R/f2

Result:

The observations from the experiment is tabulated the following

Precautions

¢ The parallax has to be removed idea to idea properly.

¢ The lens and plane looking glass should be cleaned out thouroughly.

¢ The liquid considered should be essentially transparent.

Only few drops of liquid ought to be taken so that the liquid contact lens layer is definitely not thicker

Sources of mistake:

¢ Liquid may not be quite clear

¢ The parallax any not really be fully removed

¢ The needle might not be properly horizontal

The length x1 and x2 may not be essentially clean

The research described with this project is an effective and simple technique of measuring the refractive index of any kind of liquid (transparent) using a convex lens and plane reflect. If we keep the mirror at the rear of a lens and put an object at the target point of the lens over it, the image of the thing will form at the same emphasis point in which the object is definitely. If it is a long object, their image will be inverted and the size of image is identical to that of the object. This property has allowed the successful use of the liquid lens to find the refractive index of a smooth by this method. If a liquid is placed between the lens and the reflect, the central length of liquid lens can be calculated knowing the focal length of the combination which of the convex lens, that the echoing index of the fluid are always estimated.

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