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ENGINEERING PHYSICS
LAB MANUAL
Institute Vision and Mission
Vision
To emerge as a Center of Excellence for Learning and Research in the domains of
engineering, computing and management.
Mission
Provide congenial academic ambience with state-art of resources for learning and
research.
Ignite the students to acquire self-reliance in the latest technologies.
Unleash and encourage the innate potential and creativity of students.
Inculcate confidence to face and experience new challenges.
Foster enterprising spirit among students.
Work collaboratively with technical Institutes / Universities / Industries of National
and International repute.
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CO/PO Mapping
PO1 PO2 PO3 PO4 PO5 PO6 PO7 PO8 PO9 PO10 PO11 PO12
CO1
CO2
CO3
CO4
CO5
CO6
CO7
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PROGRAM OUTCOMES (PO’s)
PO1. Engineering knowledge: Apply the knowledge of mathematics, science, engineering
fundamentals and an engineering specialization to the solution of complex engineering problems.
PO2. Problem analysis: Identify, formulate, review research literature and analyze complex
engineering problems reaching substantiated conclusions using first principles of mathematics,
natural sciences and engineering sciences.
PO3. Design/development of solutions: Design solutions for complex engineering problems and
design system components or processes that meet the specified needs with appropriate
consideration for the public health and safety and the cultural, societal and environmental
considerations.
PO4. Conduct investigations of complex problems: Use research-based knowledge and research
methods including design of experiments, analysis and interpretation of data and synthesis of the
information to provide valid conclusions.
PO5. Modern tool usage: Create, select and apply appropriate techniques, resources and modern
engineering and IT tools including prediction and modeling to complex engineering activities with
an understanding of the limitations.
PO6. The engineer and society: Apply reasoning informed by the contextual knowledge to assess
societal, health, safety, legal and cultural issues and the consequent responsibilities relevant to the
professional engineering practice.
PO7. Environment and sustainability: Understand the impact of the professional engineering
solutions in societal and environmental contexts, and demonstrate the knowledge of and need for
sustainable development.
PO8. Ethics: Apply ethical principles and commit to professional ethics and responsibilities and
norms of the engineering practice.
PO9. Individual and team work: Function effectively as an individual and as a member or leader in
diverse teams and in multidisciplinary settings.
PO10. Communication: Communicate effectively on complex engineering activities with the
engineering community and with society at large, such as, being able to comprehend and write
effective reports and design documentation, make effective presentations and give and receive
clear instructions.
PO11. Project management and finance: Demonstrate knowledge and understanding of the
engineering and management principles and apply these to one’s own work, as a member and
leader in a team, to manage projects and in multidisciplinary environments.
PO12. Life-long learning: Recognize the need for and have the preparation and ability to engage in
independent and life-long learning in the broadest context of technological change.
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4
I B.Tech I Sem L T P C
0 0 3 1
18SAH115 ENGINEERING PHYSICS LABORATORY
(Common to ECE&CSE)
Course Educational Objectives:
CEO1: To Demonstrate Knowledge on measurement of various physical quantities
using optical Methods and fundamentals of magnetic fields.
CEO2: To Identify different physical properties of materials like band gap, magnetic
field Intensity etc, for engineering and technological applications
CEO3: To provide valid conclusions on phenomena Interference and Diffraction
S.No. Name of the Experiment
1. Diffraction grating - Measurement of wavelength of given Laser.
2. Determination of magnetic field along the axis of a current carrying circular coil -
Stewart Gees method.
3. Determination of numerical aperture and acceptance angle of an optical fiber.
4. Determination of particle size using a laser source.
5. Parallel fringes – Determination of thickness of thin object using wedge method.
6. Newton‟s rings – Determination of radius of curvature of given plano convex lens.
7. B-H curve – Determination of hysteresis loss for a given magnetic material.
8. Determination of Energy band gap of semiconductor.
After completion of the laboratory course the student able to
CO 1: Demonstrate Knowledge on measurement of various physical quantities using optical
Methods and fundamentals of magnetic fields.
CO 2: Identify different physical physical properties of materials like band gap, magnetic
field Intensity etc, for engineering and technological applications.
CO3: Provide valid conclusions on phenomena Interference and Diffraction.
CO4: Follow ethical values during conducting of Experiments.
CO5: Work individually or in a team effectively.
CO6: Communicate verbally and in written form pertaining to resusults of the Experiments.
CO7: Learns to perform experiments involving physical Phenomena in future years.
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(ENGINEERING PHYSIOCS) LABORATORY MANUAL
__I_ B.TECH __ SEMESTER regulation: r16/18
Name of Student : Roll Number : Subject Code :
FACULTY INCHARGE: Designation :
DEPARTMENT:
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SITAMS
Engineering physics LABORATORY Subject Code :18SaH115
INDEX
S.No
Experiment Name K
no
wle
dg
e G
ain
ed
An
aly
sis
, D
esig
n
an
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f M
od
ern
To
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Tech
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ue
Ab
ilit
y o
f d
o
exp
erim
en
t an
d
follo
win
g o
f eth
ical
prin
cip
les
Resu
lt &
Co
nclu
sio
n
VIV
A V
OC
E
(C
om
mu
nic
ati
on
,
Lif
e L
on
g l
earn
ing
TO
TA
L
Sig
natu
re o
f th
e F
acu
lty
3 3 3 3 3 15
1 Diffraction grating - Measurement of
wavelength of given Laser.
2
Determination of magnetic field along the axis
of a current carrying circular coil - Stewart
Gees method
3 Determination of numerical aperture and
acceptance angle of an optical fiber
4 Determination of particle size using a laser
source
5 Parallel fringes – Determination of thickness
of thin object using wedge method.
6 Newton‟s rings – Determination of radius of
curvature of given Plano convex lens
7 B-H curve – Determination of hysteresis loss
for a given magnetic material.
8 Determination of Energy band gap of
semiconductor
Average
Signature of the faculty in-charge with
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SITAMS
Engineering Physics Laboratory Subject Code :
INDEX
Signature of the faculty in-charge with date
Expt.No: Date:
NEWTON’S RINGS-DETERMINATION OF RADIUS OF CURVATURE OF PLANO
CONVEX LENS
AIM:
To determine the radius of curvature of the given Plano convex lens
APPARATUS:
Plane glass plate, Plano convex lens, traveling microscope, reading lens and sodium vapor
lamp.
Sl. No. Date Name of the Experiment/Exercise Page No. Marks Signature
1 Dispersive Power of Prism – Spectrometer (Demo)
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FORMULA: The radius of curvature of the Plano convex lens
(Dm2-Dn
2)
R = cm
4(m-n)
Where = refractive index of air =1
Dm = Diameter of the mth
ring in cm
Dn = Diameter of the nth
ring in cm
= Wave length of the sodium vapor lamp.
m, n = Number of chosen rings.
Microscope
Newton’s rings
Air film
6th
3rd
3rd
6th
PROCEDURE:
1. A Glass plate is kept on a black paper. The Plano-convex lens is kept on the plane
glass plate. Another glass plate is arranged at an angle of 450 above the Plano convex
lens. This arrangement is kept in a wooden box.
2. The above unit is kept under the traveling microscope.
3. Parallel beam of monochromatic light is incident on the plane glass at 450 and hence
the beam incident normally on the plano-convex lens.
lens
Plano
Convex
lens
Glass
Plate
Lens
Source
Glass
plate
450
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4. The Plano-convex lens reflects a part of the incident light and a part of light is
transmitted, which is reflected from the surface of the plan glass plate. Hence the
interference fringes are observed through the microscope.
5. The microscope is moved to one side and the vertical cross wire is made tangential to
the 18th
, 15th
… up to 3rd
ring. The horizontal scale reading of the traveling microscope
is noted.
6. The vertical cross wire is made tangential to the other side of the rings from
3rd
,6th
,….. Up to 18th
ring.
7. The microscopic readings are noted in the tabular form. From the tabular form we can
calculate the values of Dm2-Dn
2
8. The radius of curvature of the given Plano-convex lens is determined by using the
formula
GRAPH:
Scale:
On X-axis 1-unit =
R = (Dm2-Dn
2) D
2 on Y-axia 1 unit=
cm
4(m-n) Dm2
Dn2
No. of rings
OBSERVATIONS: Wave length of sodium vapor lamp () =5896
o A
Refractive index of air () = 1
TO DETERMINE THE DIAMETER (D) OF THE DARK RING:
L.C. of the traveling microscope = 01.050
5.0
mm
N
Smm or 0.001 cm
Sl.no Ring no. Microscope reading Diameter of the
ring D in cm
x~y
D2 in cm
2 Dm
2-Dn
2
Cm2 Left
x
Right
y
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1
2
3
4
5
6
18
15
12
9
6
3
m-n = 3 Average (Dm2-Dn
2) = cm
2
PRECAUTIONS:
1.Microscope should be moved only in one direction to avoid backlash error
2. The slow motion tangential screw must be used while noting the readings
3.The readings of the central balck spot need not be consider.
RESULT:
The radius of curvature of the plano-convex lens
From experiment: cm
From graph : cm
Viva-voce Questions:
1. In the Newton‟s ring experiment, how does interference occur?
2. Where have the fringes formed?
3. Why are the fringes circular?
4. Are all rings equispaced?
5. How is the central spot in your experiment, bright or dark? Why?
6. Is it possible to determine the refractive index of the liquid by this experiment?
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Conclusion:
CO/PO Mapping
PO1 PO2 PO3 PO4 PO5 PO6 PO7 PO8 PO9 PO10 PO11 PO12
CO1
CO2
CO3
CO4
CO5
CO6
CO7
Expt.No: Date:
DETERMINATION OF WAVE LENGTH OF A LASER SOURCE USING
DIFRACITION GRATING
AIM: To determine the wavelength of given Laser source by using a plane diffraction
Grating.
APPARSTUS: Plane diffraction grating, Laser source, Grating stand, scale, screen (wall).
FORMULA:
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Wave length of Laser source nN
sin Å
Where N = No. of lines per inch on the grating
N = 15000lines / inch
N = 15000 / 2.54 lines / cm
n = Order of diffraction (or) Spot
D
dTan
d = Distance between bright central spot and
concerned order of diffraction pattern in (cm)
D = Distance between screen and grating in (cm)
Screen
Diffraction Grating
d1
D
PROCEDURE
Mount the screen, grating and source of laser inline on a optical bench. Adjust the
distance between grating and the source as 20 centimeters which is fixed one. Keep the
distance D between the screen and the grating as 40 cm. Now we can observe first order and
second order diffraction spots on either side of the central bright spot. Measure the distance
of first order diffraction spot on either side of the bright central spot and note down the
LASER
SOURCE
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reading in the tabular form. Take the average of these two distances and note down in the
tabular form. The experiment is repeated for second order spot also in the same manner.
The experiment is repeated by changing the distance D between screen and the grating in
steps of 10 cm. The distances of first order and second order spots are measured and are
averaged. The readings are tabulated in the tabular form. The wave length of laser source can
be determined by using the formula Nn
sin .
Where D
dTan
N = 15000 lines per inch on the grating.
N = 54.2
15000 lines per cm on the grating
Tabular column:
S.no Distance
between
screen
and
gratting
D
Cm
Order
of
Diffrac
tion
pattern
n
Distance between central
bright spot to concern order of
diffraction pattern d (cm) D
dTan
.
Ө= Tan-1
Ө Sin Ө
Nn
sin
nm
Left
(d1)
Right
(d2)
Mean d
=
1 2
2
d d
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Mean
Precautions:
1. Keep the distance between grating and source as constant.
2. Don‟t expose the laser light to the eyes.
RESULT:
Wave length of the given Laser source is determined and is =
Viva-Voce Questions:
1. In this experiment, how does diffraction occur?
2. What is a plane transmission diffraction grating?
3. What is a reflection grating?
4. How are commercial gratings made?
5. What type of grating do you use for your experiment?
6. Define grating element and corresponding points.
7. Distinguish between a grating spectrum and a prismatic spectrum.
8. What will happen if the slit is illuminated with white light?
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9. What is the SI unit of wavelength
Conclusion:
CO/PO Mapping
PO1 PO2 PO3 PO4 PO5 PO6 PO7 PO8 PO9 PO10 PO11 PO12
CO1
CO2
CO3
CO4
CO5
CO6
CO7
Expt.No: Date:
OPTICAL FIBERS-NUMERICAL APERTURE MEASURMENT
AIM: To determine the numerical aperture of the given optical fiber
APPARATUS: One or two meters of step index optical fiber, digital multimeter, Adopters,
Connectors, D.C power supply, Fiber optic trainer module, N.A measurement jig.
FORMULA:
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N.A =
2
1224 wL
w
Where “w” be the diameter of the light falling on the screen (mm)
“L” is the distance between the fiber end and the screen (cm)
PROCEDURE: The twist or the microbends on the fiber, if any are to be removed first. In order to
remove the twist, the optical fiber is wound on a mandrel. An adhesive tape may be used to
hold the windings on the mandral in the proper position.
One end of the optical fiber is connected to the N.A.Jig through the connector and the other
end of the fiber to the power out P0 of the N.A.module.The A.C mains is switched ON and
the light passing through the cable at the other end of (coming to the N.A.Jig) of the fiber is
observed to ensure proper coupling is made or not. The set “P0” knob is turned in the
clockwise direction to get maximum intensity of light through the fiber. The “Set P0” is to be
left free at this stage.
A screen with concentric circle of known diameter is kept vertically at a distance (L)
from the fiber end and the red spot is made exactly equal to the first concentric circle and the
corresponding distance (L) from the fiber end to the screen are noted. The diameter of the red
spot can be varied by varying the distance “L”.
The experiment is repeated for the subsequent diameter of the circles by adjusting the
length “L”. The diameter of the circle is determined using the traveling microscope.
For each set of observations, the numerical aperture is calculated using the formula
N.A =
2
1224 wL
w
230 A/C
Mandral
Connector N.A Jig
Connector
L
L
N.A
Measurement
module
SET P0
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OBSERVATION: Tabular column:
S.No
L(mm) L2 W
(mm) W2
4L2 + W2
(X) X1/2 N.A= W/X1/2
Mean N.A=
RESULT:
The numerical aperture of the given optical fiber is =
Acceptance angle 1( . )A Sin N A =
Viva-Voce Questions:
1. What is mean by “Total internal reflection”?
2. What is mean by “Numerical aperture”?
3. What is mean by “Acceptance angle”?
4. Which optical source is well suited for fiber optic communication and why?
5. What are the advantages of optical fiber over conventional communication system?
6. Why Semiconductor lasers are preferred compare to LEDs for optical fiber
communication systems?
7. Which optical fibers are suitable for long distance transmission?
8. What is mean by “Modal dispersion”?
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9. What is mean by chromatic dispersion?
10. What are the losses expected in optical fibers?
Conclusion:
CO/PO Mapping
PO1 PO2 PO3 PO4 PO5 PO6 PO7 PO8 PO9 PO10 PO11 PO12
CO1
CO2
CO3
CO4
CO5
CO6
CO7
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Expt.No: Date:
THICKNESS OF A WIRE- WEDGE METHOD
AIM: To determine the thickness of the wire by traveling microscope
APPARATUS:
Traveling microscope, plane glass plates, reading lens, sodium vapor lamp
FORMULA:
Thickness of the thin wire (t) = 2
d
cm
Where = Wave length of the sodium light
= The fringe width in cm
d = distance between the point of contact of the glass plate and the wire in cm
PROCEDURE:
Glass plate
Sodium
vapour lamp
Wire
1. Two plane glass plates are cleaned well and the given wire is arranged straightly in
between the glass plate such that the glass plates touch at one end and separated at the
0 2 4 6
Interference fringes
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other end. The distance between the point of contact of the glass plate and the wire is
determined as “d”.
2. This unit is arranged in a box in which a plane glass plate is fixed at 450 angles. This
box is kept on the base of the traveling microscope as shown in the figure.
3. By adjusting the microscope we have interference fringes as shown in figure.
4. The vertical cross wire is made to coincide with zero fringes and horizontal scale
reading of microscope is noted. In this way for every five fringes the readings are
noted in the tabular form.
5. Fringe width “” is determined from the tabular form.
6. The thickness of the wire is determined using the formula
Thickness of the thin wire (t) cm = 2
d
OBSERVATIONS:
d = cm
= 5893 x 10-8
cm.
TO DETERMINE THE FRINGE WIDTH ():
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L.C. of the traveling microscope = 01.050
5.0
mm
N
Smm or 0.001 cm
S.No No.of
the
fringes
Reading of the microscope Width of
5 fringes
In
cm
Fringe width
in cm M.S.R
(a) in cm
V.C
(n)
Fraction
n x L.C = (b)
in cm
Total
Reading
(a+b)
in cm
Average () = cm
PRECAUTIONS:
1. The wire should be thin and uniform
2. Microscope should be moved in only one direction.
3. Glass plate should be clean.
RESULT:
The thickness of the wire (t) = cm
Viva –Voce Questions:
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1. What is the principle involved in wedge film?
2. What is a wedge shaped film?
3. What is superposition principle?
4. Define interference.
5. What are coherent sources?
6. What is a mono chromatic source? Give example.
7. What is meant by least count?
8. What is the least count of traveling microscope?
9. Why a glass plate is placed at an angle 450?
10. Instead of sodium vapor lamp if we use mercury source, is there any change in fringe
pattern.
Conclusion:
CO/PO Mapping
PO1 PO2 PO3 PO4 PO5 PO6 PO7 PO8 PO9 PO10 PO11 PO12
CO1
CO2
CO3
CO4
CO5
CO6
CO7
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Expt.No: Date:
MAGNETIC FIELD ALONG THE AXIS OF A CURRENT CARRYING COIL
-STEWART&GEE’S METHOD.
AIM:
To determine the field of induction at several points on the axis of a circular coil
carrying current using Stewart and Gee‟s type of tangent galvanometer.
APPARATUS:
Stewart and Gees galvanometer, Battery eliminator, Ammeter, Commutator, Rheostat,
plug keys, scale, and connecting wires.
FORMULA:
The magnetic induction (B) at any point on the axis of the coil is
B =
2
322
2
0
2 ax
nia
µo=4πx10-7
henry-mter-1
Where i is the amount of flowing through the circular coil (amp).
n no.of turns in the coil
a radius of the coil (cm)
x distance of the point from the centre of the coil (cm)
B=Be Tanθ
Be –the horizontal component of earth‟s magnetic field=0.38x10-4
Tesla
PROCEDURE: With the help of the deflection magnetometer and a chalk, a long line about one meter
is drawn on the working table, to represent the magnetic meridian. Another line perpendicular
to this also drawn. The Stewart and Gee‟s galvanometer is set with its coil in the magnetic
meridian. The external circuit is connected as shown in figure, keeping the ammeter, rheostat
away from the deflection magnetometer. This precaution is very much required because the
magnetic field produced by the current passing through the rheostat and the permanent
magnetic field due to the magnet inside the ammeter affect the magnetometer reading, if they
are close to it.
The magnetometer is set at the centre of the coil and rotate it to make the
aluminum pointer read (0, 0) in the magnetometer. The key K, is closed and the rheostat is
adjusted so as the deflection in galvanometer is about 600.The current in the commutator is
reversed and the deflection in the magnetometer is observed .The deflection in the
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magnetometer before and after reversal of current should not differ much. In case of
sufficient difference say above 20or 3
0, necessary adjustments are to be made.
The deflections before and after reversal of current are noted when d=0.The
readings are noted in table. The magnetometer is moved towards east along the axis of the
coil in steps of 2 cm at a time. At each position, the key is close and the deflections before
and after reversal of current is noted. The mean deflection is noted as θE. The magnetometer
is further moved towards east in steps of 2 cm each time and the deflections before and after
the reversal of current is noted, until the deflection falls to 300
.
The experiment is repeated by shifting the magnetometer towards west from the
centre of the coil in steps of 2 cm, each time the deflections are noted before and after the
reversal of current .The mean deflection is θW
OBSERVATION: Current through the coil i = amp
Radius of the coil r or a = cm
No of turns in the coil n =
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ENGINEERING PHYSICS LABORATORY MANUAL
Tabular column:
RESULT: The Theoretical and Experimental values of magnetic induction field values calculated at various points on the axis of circular coil are found to
be equal.
S.No Distance of the
deflection
magnetometer
from the centre
of the coil
Deflection in the galvanometer
(East side)
Deflection in the galvanometer
(West side) 2
WE
Tan
θ
B=
Be
tan θ
B =
2
322
2
0
2 ax
nia
θ1 θ2 Θ3 θ4
Mea
n θ
E
Tan
θE
θ1 θ2 θ3 θ4
Mea
n θ
W
Tan
θW
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Viva-Voce Questions:
1. What is the principle involved in Field along the axis of a coil?
2. What is tangent law?
3. What is meant by magnetic meridian?
4. What is Biot-Savart‟s law?
5. What is Ampere‟s law?
6. What is the unit of magnetic induction „B‟?
7. What is meant by magnetic field and magnetic induction?
8. What is meant by “Tan A” position?
9. What is mean by “Tan B” position?
10. What is meant by solenoid?
Conclusion:
CO/PO Mapping
PO1 PO2 PO3 PO4 PO5 PO6 PO7 PO8 PO9 PO10 PO11 PO12
CO1
CO2
CO3
CO4
CO5
CO6
CO7
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Expt.No: Date:
DETERMINATION OF PARITCLE SIZE USING LASER
AIM: To determine the size of the particle using a LED laser source.
APPARATUS: A laser source, (p-n junction type) particle deposited slide, Screen, Optical
bench and Slide holder.
FORMULA: The size of the particle is given by
D = nr
dn22.1 m
Where Wavelength of laser light
n = Order of diffraction pattern
d = Distance from the particle slide to the screen.
rn = Radius of the nth
order.
rn
d
PROCEDURE:
Align the Laser source, particle deposited slide and screen on the optical bench in a line.
The slide is placed on the slide holder. Keep the distance between the source and screen as
nearly 100 cm. Adjust the distance between screen and slide (d) as 5cm. now laser diode is
switched on and laser light falls on the particle deposited slide.
A diffraction pattern is formed on the screen. The diameter and radius of the patterns are
noted down in the tabular form, for 1st order and 2nd
order respectively.
LASER
SOURCE
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The experiment is repeated for various values of d in steps of 5cm. and the readings are
tabulated.
The particle size can be calculated by using the formula
D = nr
dn22.1 m
The mean value of size of the particle can be calculated.
OBSERVATION:
Tabular Form:
Particle
deposited
slide No.
d
(cm)
Order of the
diffraction
pattern
Diameter of
the diffraction
pattern in mm
Radius of
the
diffraction
pattern in
mm
D = nr
dn22.1
PRECAUTIONS: Mean D=
1.Skin should not be exposed to laser light.
2.laser light should not be focused on to the eyes.
RESULT:
The size of particle is determined and is =
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Viva-Voce Questions:
1. Why laser sources are well suited for diffraction techniques?
2. What is mean by diffraction?
3. What are the types of diffraction possible?
4. What are the differences between interference and diffraction?
5. What are conditions to get maxima and minima?
6. What are the characteristics of laser?
7. Give the differences between LED& LASER
8. What are coherent sources?
9. What is mean by laser?
10. What are the conditions to get diffraction?
Conclusion:
CO/PO Mapping
PO1 PO2 PO3 PO4 PO5 PO6 PO7 PO8 PO9 PO10 PO11 PO12
CO1
CO2
CO3
CO4
CO5
CO6
CO7
SREENIVASA INSTITUTE OF TECHNOLOGY AND MANAGEMENT STUDIES-CHITTOOR
(AUTONOMOUS)
30
EXPT.NO: Date:
ENERGY GAP OF A SEMICONDUCTOR
(P-N JUNCTION DIODE)
AIM: To determine the energy gap of a semiconductor material taken in form of p - n
junction diode.
APPARATUS: Energy gap of a semiconductor Trainer kit, Heating arrangement to heat the
diode, Connecting wires.
FORMULA:
Energy gap of a Semiconductor Diode eVX
SlopeKEg 19106.1
**2*303.2
Where Slope =
T
sI
1
log10
Is – Saturation Current through the diode (A).
T – Absolute Temperature (oK).
Circuit Diagram:
PROCEDURE:
Connect the terminals of the given semiconductor diode (Ge or Si) to the D.C Power
supply and micro ammeter in such a way that the diode is reverse biased. Immerse the diode
in the oil bath. Insert the Thermometer in the oil bath at the same level as that of the diode as
shown in fig 1.
Switch on the D.C Power supply and adjust the reverse bias voltage to 5 Volt. Switch
on the A.C. Main supply, then the temperature of the oil batch gradually increases. When the
temperature of the oil bath reachs the about 65oc, then switch off the A.C. supply.Stirr the oil
by means of a Stirrer. Then, the temperature of the oil bath will rise and stabilizes at about
80oc.
Table 1: To determine the Reverse Saturation Current at different temperatures.
Type of the Diode:____ , Biasing Voltage: 5 volt., Room Temperature =_______ oC
SREENIVASA INSTITUTE OF TECHNOLOGY AND MANAGEMENT STUDIES-CHITTOOR
(AUTONOMOUS)
31
S.No.
Temperature Current 1/T(K
-1)
sI
10log t (oC) T=t+273(
oK) Is(A)
1 2 3 4 5 6 7 8
Note the temperature of the oil bath and the current through the diode. After few minutes, the
temperature of the oil batch will begin to fall and the current through the diode decreases.
Note the value of the current for every 5oc decrease of the temperature, till the temperature of
the oil bath falls to the room temperature. Note the observations in Table1.
Model Graph:
Draw the Graph between the inverse of temperature and the Logarithm of the Current
for different temperatures as shown in below fig.2. Take the slope from the graph.
precautions:
1. Note the readings with-out parallex errors.
2. Temperature should be in the range of 40oc
to 95oc
3. Diode must be connected in reverse bias condition.
Result:
SREENIVASA INSTITUTE OF TECHNOLOGY AND MANAGEMENT STUDIES-CHITTOOR
(AUTONOMOUS)
32
Conclusion:
CO/PO Mapping
PO1 PO2 PO3 PO4 PO5 PO6 PO7 PO8 PO9 PO10 PO11 PO12
CO1
CO2
CO3
CO4
CO5
CO6
CO7
SREENIVASA INSTITUTE OF TECHNOLOGY AND MANAGEMENT STUDIES-CHITTOOR
(AUTONOMOUS)
33
Expt.No. Date:
B-H LOOP
Aim: To Trace the B-H Loop and find the area of the loop.
Apparatus: B-H loop kit, CRO, CRO X,Y probes, and trace paper.
Theory: There are two windings on the specimen . The primary is fed with low AC voltage.
This produces a magnetic field H in the specimen. The voltage across R is connected in series
with primary is proportional to magnetic field. This is given to X input of CRO.
This magnetic field induces a voltage in the secondary coil. This induced voltage is
proportional to Magnetic induction field strength (B).Thus this output is proportional to B.
This is fed to Vertical input of CRO(Y input).
The applied voltage is directly proportional to H in horizontal axis and voltage is directly
proportional to B in the vertical axis. Hence a loop is formed. This gives area under the loop
and this gives loss of energy in the Specimen.
Procedure:
The connections are made as per the kit diagram. The CRO probes are connected with respect
to X and Y channels. The Probes are connected as indicated in the kit.
A loop is formed on the CRO Screen. This is traced onto a transparent paper. This is redrawn
on a ordinary graph paper. Now the small squares are counted in number which gives raise to
area of the loop in Square mm. This is converted to m2.
Result: B-H loop is observed and is traced with a trace paper. The area of the loop is
calculated by drawing loop on a plain graph sheet.
Area of the B-H loop=
Conclusion:
CO/PO Mapping
PO1 PO2 PO3 PO4 PO5 PO6 PO7 PO8 PO9 PO10 PO11 PO12
CO1
CO2
CO3
CO4
CO5
CO6
CO7
SREENIVASA INSTITUTE OF TECHNOLOGY AND MANAGEMENT STUDIES-CHITTOOR
(AUTONOMOUS)
34
SREENIVASA INSTITUTE OF TECHNOLOGY AND MANAGEMENT STUDIES-CHITTOOR
(AUTONOMOUS)
35
TABLE1: RUBRICS FOR ENGINEERING PHYSICS LAB
Excellent(3) Good(2) Fair(1)
Conduct
Experiments
(CO1)
Student successfully
completes the drawings
and explains the
experiment concisely and
well.
Student successfully
completes the
drawings and
explains the
experiment
moderately.
Student successfully
completes the drawings
and unable to explain
the experiment.
Analysis and
Synthesis
(CO2)
Analysis the drawing in
detail thoroughly.
Reasonable analysis
of the drawing.
Improper analysis of the
drawing.
Design
(CO3)
Students successfully
complete the design and
explain the design process
in brief and well.
Students successfully
complete the design
and explain
appropriate design
process.
Students successfully
complete the design and
unable to explain design
process.
Use modern
tools in
engineering
practice
(CO4)
Students used many
modern tools to complete
the drawing.
Students used few
modern tools to
complete the
drawing.
Students not used
modern tools to
complete the drawing.
Ethics and Lab
safety
(CO5)
Student will demonstrate
good
understanding and follow
lab ethics and safety
Student will
demonstrate good
understanding of lab
ethics and safety
Students demonstrate a
little knowledge of lab
ethics and safety.
Ability to
work as
individual
(CO6)
Ability to Perform the
drawing as an individual
with clear proof of tasks
and effort
Ability to Perform the
drawing as an
individual with
moderate proof of
tasks and effort.
Ability to Perform the
drawing as an individual
without proof of tasks
and effort.
Report Writing
(CO7)
Generate the report with
clear procedure of the
experiment using excellent
language.
Generate the report
with clear procedure
of the experiment
using understandable
language
Generate the report with
improper organized.
Continuous
learning
(CO8)
Highly enthusiastic
towards continuous
learning
Interested in
continuous learning
Inadequate interest in
continuous learning
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