engineering physics laboratory manual

SREENIVASA INSTITUTE OF TECHNOLOGY AND MANAGEMENT STUDIES

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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

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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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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

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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:

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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:

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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 =


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:

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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:

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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 =

SREENIVASA INSTITUTE OF TECHNOLOGY AND MANAGEMENT STUDIES-CHITTOOR (AUTONOMOUS)

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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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:

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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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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:

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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


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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:


(AUTONOMOUS)

32

Conclusion:

CO/PO Mapping


CO1

CO2

CO3

CO4

CO5

CO6

CO7


(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


CO1

CO2

CO3

CO4

CO5

CO6

CO7


(AUTONOMOUS)

34


(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.


completes the

drawings and

explains the

experiment

moderately.


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.


complete the design

and explain

appropriate design

process.


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


drawing as an

individual with

moderate proof of

tasks and effort.


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

engineering physics laboratory manual

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