SCHOOL NAME SCHOOL NAME SCHOOL NAME - ammhu.com Prism104.pdfA hollow prism, translucent liquids (e.g., water, any oil such as oil, kerosene oil or turpentine oil and glycerin)whose

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www.ammhu.com A categorized blogging website and an Online Resource Centre For CBSE, RBSE, and Other State Boards — Raj Kumar Parashari, Head Science @ JPHS, Jaipur-302021

SCHOOL NAME SCHOOL NAME SCHOOL NAME

ADDRESS WITH PINCODE AND PHONE NUMBER

Submitted by Guided by

Student Name [ ]

Class With Section Teacher Name

Class Roll No. Designation

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Board Roll No.

INDEX

1. CERTIFICATE

2. ACKNOWLEDGEMENT

3. AIM

4. APPARATUS REQUIRED

5. PRINCIPLE / THEORY

6. RAY DIAGRAMS & IMAGES

7. PROCEDURE

8. OBSERVATIONS

9. CALCULATIONS

10. RESULT

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CERTIFICATE

This is to certify that _______________________

student of ______ school name _______, class XII Sc __

has carried out his work for the investigatory project

entitled _______________________________________

under my guidance and supervision.

Signature of the Teacher

Designation

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ACKNOWLEDGEMENT I __________________________________ a student of

____________________________________,______________

would like to pay my sincere gratitude to my Physics teacher

Mr. __________________________ for helping and guiding

me throughout the completion of the project report. I would

like to thank Mr./Mrs. _______________________ our school

principal/Director for making school such a wonderful place of

learning. I also would like to thank Mr. ________________

our lab assistant for the timely assistant in completion of the

project.

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AIM (i) To investigate the dependence of the angle of deviation

with the angle of incidence, using a hollow prism filled with

different liquids one by one and

(ii) to calculate their respective refractive indexes.

APPARATUS REQUIRED A hollow prism, translucent liquids (e.g., water, any oil such

as oil, kerosene oil or turpentine oil and glycerin)whose

refractive index is to be find, A laser light/ all pins,

protector, meter scale and plane sheets.

THEORY (i) When a ray of light RQ is incident on a prism of denser

medium at a certain angle of incidence, it is refracted along

QS towards the normal at the point of incidence. This ray is

then incident on the second face. Since it is traveling form

denser to rarer medium, it bends away from the normal and

emerges along ST. Angle of deviation δ is the angle between

the incident ray produced forward and the emergent ray

produced backwards. The TFK= δ is the angle of the

deviation. Ray diagram for the refraction through prism is

shown following

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i

m

1r 2r

1P

2P3

P

4P

1N

2N

3N

i

For the refraction through the prism, the relation always

applicable is

i +e = A+ δ

where, i = angle of incidence

A = prism angle

e = angle of emergence

δ = angle of deviation

When the angle of incidence is changed, angle of deviation

also changes, which graphically is represented as follows;

(ii) From the graph it is obvious that with increase in angle

of incidence angle of deviation first decreases , takes the

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minimum value and then increases. If m be the minimum

value of angle of deviation then, the refractive index of the

material of the given prism is given by;

mAsin

2

Asin

2

-------------- (1)

PROCEDURE

(i) Fill the hollow prism with water first.

(ii) Fix the white sheet of paper on the drawing board with

drawing pins.

(iii) Place the prism on this white sheet and mark the boundary

ABC of the prism.

(iv) Lift the prism and mark a point Q in the middle of AB.

Draw perpendicular QN1 on AB.

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(v) Draw a line QR making an angle 35 with QN1. Fix two

office pins P1 and P2 on QR with distance more than 10cm

between P1 and P2.

(vi) Now, place the prism on its boundary ABC. Seeing through

the face AC, fix two more pins P3 and P4 in such a way that the

images of P1 and P2 are in line with P3 and P4, i.e., the feet of all

the four pins should be in a straight line.

(vii) Remove P3 and P4 and join their positions to make a line

ST. .

(viii)Produce RQ and TS so that the two meet at F.

(ix) As shown in fig, measure angle of incidence N1QR = i

and angle of deviation KFS = δ.

(x) 0Measure the value of angle of angle of deviation with the

help of protractor.

(xi) Measure the angle of prism (A) between the refracting

faces AB and AC of the prism.

(xii) Repeat this process with different value of angle i and

measure angle respectively.

(xiii)Increase the value of angle i by 5 each time.

(xiv) Record the observations in tabular form.

(xv) Plot a graph between the angle of incidence i (along x-axis)

and angle of deviation (along y-axis). This graph obtained will

be as shown in the figure below.

(xvi) Note the value of the angle of minimum deviation δm from

the graph corresponding to the lowest point of the i- curve as

shown.

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(xvii) Repeat the experiment by replacing water in the hollow

prism by filling any type of transparent oil and then with

glycerin.

Observations:—

Liquid S. No. Angle of

Incidence(i)

Angle of

deviation( )

Water 1. 30°

2. 35°

3. 40°

4. 45° 5. 50°

6. 55° Oil 1. 30°

2. 35° 3. 40°

4. 45° 5. 50° 6. 55°

Glycerin 1. 30°

2. 35°

3. 40°

4. 45° 5. 50° 6. 55°

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Result-

(1) The graph between i and for each liquid

shows that as the angle of incidence increases,

the angle of deviation first decreases and

attains a minimum value m and then

increases.

(2) The angle of minimum deviation from the

graph for

(i) Water-

(ii) Oil -

(iii) Glycerin –

(3) The refractive indexes of the liquids under

consideration are

(i) µWater =

(ii) µOil =

(iii) µGlycerin =

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Bibliography

1.

2.

3.

Note: — Hand written Investigatory Project

Report should be submitted. Work should be

neat and clean. Avoid unnecessary fancy

decoration of the project report.

Note: — Take readings, draw graph for each

between angle of deviation v/s angle of

incidence for each liquid. Find angle of

minimum deviation for each liquid, Do

analysis and requires calculations to complete

your project as suggested.

Note: — Learn theory, working and related

viva for board practical examination.

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Wish you all the best.

Raj Kumar Parashari

Head Science

JPHS, Jaipur

Documents

SCHOOL NAME SCHOOL NAME SCHOOL NAME - ammhu.com Prism104.pdfA hollow prism, translucent liquids (e.g., water, any oil such as oil, kerosene oil or turpentine oil and glycerin)whose