Name: Arya Sarkar

Class: XII
Section: Medical
Roll: 14
Subject: Physics Investigatory Project
Session: 2023-24
 Acknowledgement
I owe a great many thanks to great many people
who helped and supported me during this project.
I express my thanks to Principal sir, Dr. Sujit Kumar
Jana for extending his support.
My deepest thanks to Mr. Tanmay Sau , our Physics
teacher, the guide
of the project for guiding and correcting my various
documents with attention and care. He has taken
pain to go through the project and make
correction as and when needed.
INDEX:

Page
Sl.No Topic No.
1. Aim 5
2 Introduction 6-8
3. Apparatus required 9
and theory
4. Procedure 10-11
5. Observation 11-12
6. Conclusion 12
Precautions and 13
sources of error
7. Bibliography 14
AIM:-
To investigate the
Dependence Of the
angle of deviation
On the
angle of incidence
using a hollow prism
filled one by one
with different
transparent fluids
INTRODUCTION
In optics, a prism is a transparent optical
element with flat, polished surfaces that
refracts light. The exact angles between the
surfaces depend on the application. The
traditional geometrical shape is that of a
triangular prism with a triangular base and
rectangular sides, and in daily use prism
usually refers to this type. Some types of
optical prism are not in fact in the shape
of geometric prisms. Prisms can be made
from any material that is transparent to the
wavelengths for which they are designed.
Typical materials include glass, plastic and
fluorite. Prism can be used to break light up
into its constituent spectral colors. Prisms
can also be used to reflect light, or to split
light into components with different
polarizations.
When light travels from one medium to
another, there is a change in the speed of
light. This change in the speed of light
causes the light to get refracted and enter
the new medium with a different angle. The
angle at which the light hits the surface of
the medium and the ratio of refractive
indices determines the degree of bending of
the refracted light. There will be a change in
the refractive index of many materials (e.g.,
glass) when lights of different wavelengths
are used. This is the reason for each colour
or different wavelengths making up the
white light to be refracted at different
angles.
When a narrow beam of white light is
incident on a prism, the emerging light is
found to consist of seven prominent colours
in the order of violet, indigo, blue, green,
yellow, orange and red. The violet colour
with the shortest wavelength bends the
most, and the longest wavelength, red,
bends the least. This phenomenon of
splitting white light into constituent colours
is called dispersion.
Prism is sometimes used as a reflector of
light rather than dispersion. If the light rays
that enter the prism hit the surface at an
angle greater than the critical angle, there
will be total internal reflection.
AIM: To investigate the dependence of the
angle of deviation on the angle of incidence
using a hollow prism filled with different
transparent fluids.

APPARATUS REQUIRED:
Drawing board, white sheets of paper prism
drawing pins, pencil, half meter scale,
thump pins, graph paper sand a protractor.

Theory:
A prism is a transparent optical element with
flat, polished surfaces that refract light. Prisms
can be made from any material that is
transparent including glass, plastic and fluorite.
A prism can be used to break light up into its
constituent spectral colors. Prism scan also be
used to reflect light, or to split light into
components with different polarizations.The
refractive index of the liquid is given by the
formula:
Procedure:
1) Fix a white sheet of paper on the drawing
board with help of drawing pins.
2) Keep the prism and mark the outline of it
as ABC.
3) Drop a normal PQ on the side AB.
4) Draw the angle of incidence in accordance
with the normal PQ and place 2 pins so
that they appear to be in the straight line.
5) Place the prism filled with given sample of
liquid, on the marked outline ABC.
 6) Now take the pins and place them on the
side AC so that all the 4 pins appear to be
in same line.
7) Remove the prism and draw the line
joining the points so obtained.
8) Mark the diagram.
9) Repeat this with different liquids and
different angle of incidence.

Observation:

U=sin((60+40)/2)/sin(30)= 1.504
U=sin((60+22)/2)/sin(30)= 1.306

Conclusion:
Benzaldehyde-
Actual: 1.546
Experimental: 1.504

Water -
Actual: 1.33
Experimental: 1.306
Precautions:
1) Angle of incidence should lie b/w 35-60
degree.
2) Pins should be vertically fixed and should
lie in same line.
3) Distance b/w two points should not be less
than 10mm.
4) Same angle of prism should be used for all
observation.
5) Arrow head should be marked to represent
emergent and incident ray.

SOURCES OF ERRORS:
1) Pin pricks may be thick.
2) Measurement of angles may be wrong.
 BIBLIOGRAPHY
1) https://en.wikipedia.org/wiki/Prism_
(optics)
2) https://byjus.com/jee/prism/
3) Comprehensive: Practical Physics
Class XII
4) https://www.studymode.com/essays/De
viation-Of-Angle-Of-Incidence-
56520279.html