SlideShare a Scribd company logo
1 of 16
2013-14
RAHUL
KUSHWAHA
KV NO.2, NSB,
VISAKHAPATNAM
PHYSICS
INVESTIGATORY PROJECT
KENDRIYA VIDYALAYA NO. 2
NAUSENABAUGH, VISAKHAPATNAM
DEPARTMENT OF PHYSICS
CERTIFICATE
This is to certify that RAHUL KUSHWAHA, a student of class XII-A has
successfully completed the research on the below mentioned project under the
guidance of MR. RAMNA RAO ( Subject Teacher ) during the year 2013-14 in
partial fulfillment of physics practical examination conducted by AISSCE, New
Delhi.
Signature of external examiner Signature of physics teacher
ACKNOWLEDGEMENT
In the accomplishment of this project successfully, many
people have best owned upon me their blessings and the heart
pledged support, this time I am utilizing to thank all the
people who have been concerned with project.
Primarily I would thank god for being able to complete this
project with success. Then I would like to thank my principal
Mr. S.V.Babu and physics teacher Mr.Ramna Rao, whose
valuable guidance has been the ones that helped me patch this
project and make it full proof success his suggestions and his
instructions has served as the major contributor towards the
completion of the project.
Then I would like to thank my parents and friends who have
helped me with their valuable suggestions and guidance has
been helpful in various phases of the completion of the project.
Last but not the least I would like to thank my classmates
who have helped me a lot.
INDEX
1.CERTIFICATE OF EXCELLENCE
2. ACKNOWLEDGEMENT
3. AIM OF PROJECT
4. INTRODUCTION
5. THEORY
6. APPARATUS REQUIRED
7. PROCEDURE FOLLOWED
8. OBSERVATION
9. CONCLUSION
10. PRECAUTION
11. BIBLIOGRAPHY
INTRODUCTION
The transformer is a device used for converting a low alternating
voltage to a high alternating voltage or vice-versa.
A Transformer based on the Principle of mutual induction according
to this principle, the amount of magnetic flux linked with a coil
changing, an e.m.f is induced in the neighboring coil.
A transformer is an electrical device which is used for
changing the A.C. voltages. A transformer is most widely used device
in both low and high current circuit. As such transformers are built
in an amazing strength of sizes. In electronic, measurement and
control circuits, transformer size may be so small that it weight only
a few tens of grams where as in high voltage power circuits, it may
weight hundred of tones.
In a transformer, the electrical energy transfer from one
circuit to another circuit takes place without the use of moving parts.
A transformer which increases the voltages is called a step-
up transformer. A transformer which decreases the A.C. voltages is
called a step-down transformer.
Transformer is, therefore, an essential piece of apparatus
both for high and low current circuits.
OBJECTIVE
To investigate the relation between the ratio of –
1. Input and output voltage.
2. Number of turnings in the secondary coil and primary coil of
a self made transformer.
When an altering e.m.f. is supplied to the primary coil p1p2, an
alternating current starts falling in it. The altering current in the
primary produces a changing magnetic flux, which induces altering
voltage in the primary as well as in the secondary. In a good-
transformer, whole of the magnetic flux linked with primary is also
linked with the secondary, and then the induced e.m.f. induced in
each turn of the secondary is equal to that induced in each turn of
the primary. Thus if Ep and Es be the instantaneous values of the
e.m.f.’s induced in the primary and the secondary and Np and Ns are
the no. of turns of the primary secondary coils of the transformer
and
dф / dt = rate of change of flux in each turnoff
the coil at this instant, we have
Ep = -Np dф/dt _______________ (1) and
Es = -Ns dф/dt _______________ (2)
Since the above relations are true at every instant, so by dividing 2
by 1, we get
Es / Ep = - Ns / Np ______________ (3)
As Ep is the instantaneous value of back e.m.f induced in the
primary coil p1, so the instantaneous current in primary coil is due to
the difference (E – Ep ) in the instantaneous values of the applied and
back e.m.f. further if Rp is the resistance o, p1p2 coil, then the
instantaneous current Ip in the primary coil is given by
Ip = E – Ep / Rp
E – Ep = Ip Rp
When the resistance of the primary is small, Rp Ip can be neglected so
therefore
E – Ep = 0 or Ep = E
Thus back e.m.f = input e.m.f
Hence equation 3 can be written as
Es / Ep = Es / E = output e.m.f / input e.m.f = Ns / Np = K
Where K is constant, called turn or transformation ratio.
IN A STEP-DOWN TRANSFORMER
Es < E so K < 1, hence Ns < Np
If Ip = value of primary current at the same instant
And Is = value of secondary current at this instant, then
Input power at the instant = Ep Ip and
Output power at the same instant = Es Is
If there are no losses of power in the transformer, then
Input power = output power Or
Ep Ip = Es Is Or
Es / Ep = Ip / Is = K
IN A STEP-UP TRANSFORMER
Es > E so K > 1, hence Ns > Np
As, k > 1, so Ip > Is or Is < Ip
i.e. current in secondary is weaker when secondary voltage is
higher.
Hence, whatever we gain in voltage, we lose in current in the
same ratio.
Similarly it can be shown, that in a step down transformer,
whatever we lose in voltage, we gain in current in the same
ratio.
Thus a step up transformer in reality steps down the current &
a step down transformer steps up the current.
EFFICIENCY
Efficiency of a transformer is defined as the ratio of output power to
the input power.
i.e.
η = output power / input power = Es Is / Ep Ip
Thus in an ideal transformer, where there is no power losses, η = 1.
But in actual practice, there are many power losses; therefore the
efficiency of transformer is less than one.
ENERGY LOSSES
Following are the major sources of energy loss in a transformer:
1. Copper loss is the energy loss in the form of heat in the copper coils
of a transformer. This is due to joule heating of conducting wires.
2. Iron loss is the energy loss in the form of heat in the iron core of
the transformer. This is due to formation of eddy currents in iron
core. It is minimized by taking laminated cores.
3. Leakage of magnetic flux occurs inspite of best insulations.
Therefore, rate of change of magnetic flux linked with each turn of
S1S2 is less than the rate of change of magnetic flux linked with
each turn of P1P2.
4. Hysteresis loss is the loss of energy due to repeated
magnetization and demagnetization of the iron core when A.C. is fed
to it.
5. Magneto striation i.e. humming noise of a transformer.
APPARATUS REQUIRED
IRON ROD
COPPER WIRE
VOLTMETER AMMETER
CIRCUIT DIAGRAM
PROCEDURE
1. Take thick iron rod and cover it with a thick paper and wind a
large number of turns of thin Cu wire on thick paper (say 60). This
constitutes primary coil of the transformer.
2. Cover the primary coil with a sheet of paper and wound relatively
smaller number of turns (say 20) of thick copper wire on it. This
constitutes the secondary coil. It is a step down transformer.
3. Connect p1, p2 to A.C main and measure the input voltage and
current using A.C voltmeter and ammeter respectively.
4. Similarly, measure the output voltage and current through s1and
s2.
5. Now connect s1and s2to A.C main and again measure voltage
and current through primary and secondary coil of step
up transformer.
6. Repeat all steps for other self made transformers by changing
number of turns in primary and secondary coil.
USES OF TRANSFORMER
A transformer is used in almost all a.c. operations-
In voltage regulator for T.V., refrigerator, computer, air
conditioner, etc.
 A step down transformer is used for welding purposes.
 A step down transformer is used for obtaining large
current.
 A step up transformer is used for the production of X-Rays
and NEON advertisement.
 Transformers are used in voltage regulators and stabilized
power supplies.
 Transformers are used in the transmissions of a.c. over
long distances.
Small transformers are used in Radio sets, telephones, loud
speakers and electric bells etc
SOURCES OF ERROR
1. Values of current can be changed due to heating effect.
2. Eddy current can change the readings.
1. The output voltage of the transformer across the secondary coil
depends upon the ratio (Ns/Np) with respect to the input voltage
2. The output voltage of the transformer across the secondary coil
depends upon the ratio (Ns/N p) with respect to the input voltage
3. There is a loss of power between input and output coil of a
transformer.
________________________________________________________________________
________________________________________________________________________
PRECAUTIONS
1. Keep safe yourself from high voltage.
2. While taking the readings of current and voltage the A.C
should remain constant.
CONCLUSION
1) NCERT textbook class 12
2) NCERT physics lab Manuel
3) INTERNET
4) www.yahoo.com
5) www.scribd.com
6) www.google.com
BIBLIOGRAPHY
HELP FROM
INTERNET
INFORMATION
FROM LIBRARY
HELP FROM
TEACHERS
Physics Investigatory Project Class 12

More Related Content

What's hot

cbse 12th chemistry investigatory project
cbse 12th chemistry investigatory project cbse 12th chemistry investigatory project
cbse 12th chemistry investigatory project NIKHIL DWIVEDI
 
TOPIC-To investigate the relation between the ratio of :- 1. Input and outpu...
TOPIC-To investigate the relation between the ratio of :-1. Input and outpu...TOPIC-To investigate the relation between the ratio of :-1. Input and outpu...
TOPIC-To investigate the relation between the ratio of :- 1. Input and outpu...CHMURLIDHAR
 
CBSE Class XII Physics Investigatory Project
CBSE Class XII Physics Investigatory ProjectCBSE Class XII Physics Investigatory Project
CBSE Class XII Physics Investigatory ProjectVaibhav Kandwal
 
PREPARATION OF SOYBEAN MILK AND ITS COMPARISION WITH NATURAL MILK
PREPARATION OF SOYBEAN MILK AND ITS COMPARISION WITH NATURAL MILKPREPARATION OF SOYBEAN MILK AND ITS COMPARISION WITH NATURAL MILK
PREPARATION OF SOYBEAN MILK AND ITS COMPARISION WITH NATURAL MILKRajivSingh261
 
Biology investigatory project xii on Drug Addiction
Biology investigatory project xii on Drug AddictionBiology investigatory project xii on Drug Addiction
Biology investigatory project xii on Drug AddictionKhalifa Shameer
 
TO STUDY THE QUANTITY OF CASEIN PRESENT IN DIFFERENT SAMPLES OF MILK
TO STUDY THE QUANTITY OF CASEIN PRESENT IN DIFFERENT SAMPLES OF MILKTO STUDY THE QUANTITY OF CASEIN PRESENT IN DIFFERENT SAMPLES OF MILK
TO STUDY THE QUANTITY OF CASEIN PRESENT IN DIFFERENT SAMPLES OF MILKAnkitSharma1903
 
Presence Of Oxalate Ions In Guava
Presence Of Oxalate Ions In Guava Presence Of Oxalate Ions In Guava
Presence Of Oxalate Ions In Guava adharshvg
 
Chemistry Investigatory Project of class 12th CBSE
Chemistry Investigatory Project  of class 12th CBSEChemistry Investigatory Project  of class 12th CBSE
Chemistry Investigatory Project of class 12th CBSENagesh Agrawal
 
Study Of oxalte ion in guava fruit at different stages of ripening
Study Of oxalte ion in guava fruit at different stages of ripeningStudy Of oxalte ion in guava fruit at different stages of ripening
Study Of oxalte ion in guava fruit at different stages of ripeningPrince Warade
 
Chemistry Investigatory Project on COLD DRINKS
Chemistry Investigatory Project on COLD DRINKSChemistry Investigatory Project on COLD DRINKS
Chemistry Investigatory Project on COLD DRINKSNaveen R
 
To Study the earth's magnetic field using a tangent galvanometer Tangent galv...
To Study the earth's magnetic field using a tangent galvanometer Tangent galv...To Study the earth's magnetic field using a tangent galvanometer Tangent galv...
To Study the earth's magnetic field using a tangent galvanometer Tangent galv...Arjun Kumar Sah
 
FARADAY LAW OF ELECTROMAGNETIC INDUCTION CLASS 12 PROJECT
FARADAY LAW OF ELECTROMAGNETIC INDUCTION CLASS 12 PROJECTFARADAY LAW OF ELECTROMAGNETIC INDUCTION CLASS 12 PROJECT
FARADAY LAW OF ELECTROMAGNETIC INDUCTION CLASS 12 PROJECTAjay Kumar
 
Chemistry project part 1 caseins in milk......
Chemistry project part 1 caseins in milk......Chemistry project part 1 caseins in milk......
Chemistry project part 1 caseins in milk......AnuragSharma530
 
PHYSICS INVESTIGATORY PROJECT 2017-18
PHYSICS INVESTIGATORY PROJECT 2017-18PHYSICS INVESTIGATORY PROJECT 2017-18
PHYSICS INVESTIGATORY PROJECT 2017-18HIMANSHU .
 
Rectifier class 12th physics investigatory project
Rectifier class 12th physics investigatory projectRectifier class 12th physics investigatory project
Rectifier class 12th physics investigatory projectndaashishk7781
 
“To estimate the charge induced on each one of the two identical Styrofoam (o...
“To estimate the charge induced on each one of the two identical Styrofoam (o...“To estimate the charge induced on each one of the two identical Styrofoam (o...
“To estimate the charge induced on each one of the two identical Styrofoam (o...VanshPatil7
 
Physics investigatory project class 12th.pdf
Physics investigatory project class 12th.pdfPhysics investigatory project class 12th.pdf
Physics investigatory project class 12th.pdfAtharvGupta31
 
Physics Practical File - with Readings | Class 12 CBSE
Physics Practical File - with Readings | Class 12 CBSEPhysics Practical File - with Readings | Class 12 CBSE
Physics Practical File - with Readings | Class 12 CBSESaksham Mittal
 
Sterlization of water using bleaching powder
Sterlization of water using bleaching powder Sterlization of water using bleaching powder
Sterlization of water using bleaching powder Gaurav Sharma
 

What's hot (20)

cbse 12th chemistry investigatory project
cbse 12th chemistry investigatory project cbse 12th chemistry investigatory project
cbse 12th chemistry investigatory project
 
TOPIC-To investigate the relation between the ratio of :- 1. Input and outpu...
TOPIC-To investigate the relation between the ratio of :-1. Input and outpu...TOPIC-To investigate the relation between the ratio of :-1. Input and outpu...
TOPIC-To investigate the relation between the ratio of :- 1. Input and outpu...
 
CBSE Class XII Physics Investigatory Project
CBSE Class XII Physics Investigatory ProjectCBSE Class XII Physics Investigatory Project
CBSE Class XII Physics Investigatory Project
 
PREPARATION OF SOYBEAN MILK AND ITS COMPARISION WITH NATURAL MILK
PREPARATION OF SOYBEAN MILK AND ITS COMPARISION WITH NATURAL MILKPREPARATION OF SOYBEAN MILK AND ITS COMPARISION WITH NATURAL MILK
PREPARATION OF SOYBEAN MILK AND ITS COMPARISION WITH NATURAL MILK
 
Biology investigatory project xii on Drug Addiction
Biology investigatory project xii on Drug AddictionBiology investigatory project xii on Drug Addiction
Biology investigatory project xii on Drug Addiction
 
TO STUDY THE QUANTITY OF CASEIN PRESENT IN DIFFERENT SAMPLES OF MILK
TO STUDY THE QUANTITY OF CASEIN PRESENT IN DIFFERENT SAMPLES OF MILKTO STUDY THE QUANTITY OF CASEIN PRESENT IN DIFFERENT SAMPLES OF MILK
TO STUDY THE QUANTITY OF CASEIN PRESENT IN DIFFERENT SAMPLES OF MILK
 
Presence Of Oxalate Ions In Guava
Presence Of Oxalate Ions In Guava Presence Of Oxalate Ions In Guava
Presence Of Oxalate Ions In Guava
 
Chemistry Investigatory Project of class 12th CBSE
Chemistry Investigatory Project  of class 12th CBSEChemistry Investigatory Project  of class 12th CBSE
Chemistry Investigatory Project of class 12th CBSE
 
Study Of oxalte ion in guava fruit at different stages of ripening
Study Of oxalte ion in guava fruit at different stages of ripeningStudy Of oxalte ion in guava fruit at different stages of ripening
Study Of oxalte ion in guava fruit at different stages of ripening
 
Chemistry Investigatory Project on COLD DRINKS
Chemistry Investigatory Project on COLD DRINKSChemistry Investigatory Project on COLD DRINKS
Chemistry Investigatory Project on COLD DRINKS
 
To Study the earth's magnetic field using a tangent galvanometer Tangent galv...
To Study the earth's magnetic field using a tangent galvanometer Tangent galv...To Study the earth's magnetic field using a tangent galvanometer Tangent galv...
To Study the earth's magnetic field using a tangent galvanometer Tangent galv...
 
FARADAY LAW OF ELECTROMAGNETIC INDUCTION CLASS 12 PROJECT
FARADAY LAW OF ELECTROMAGNETIC INDUCTION CLASS 12 PROJECTFARADAY LAW OF ELECTROMAGNETIC INDUCTION CLASS 12 PROJECT
FARADAY LAW OF ELECTROMAGNETIC INDUCTION CLASS 12 PROJECT
 
Chemistry project part 1 caseins in milk......
Chemistry project part 1 caseins in milk......Chemistry project part 1 caseins in milk......
Chemistry project part 1 caseins in milk......
 
PHYSICS INVESTIGATORY PROJECT 2017-18
PHYSICS INVESTIGATORY PROJECT 2017-18PHYSICS INVESTIGATORY PROJECT 2017-18
PHYSICS INVESTIGATORY PROJECT 2017-18
 
Rectifier class 12th physics investigatory project
Rectifier class 12th physics investigatory projectRectifier class 12th physics investigatory project
Rectifier class 12th physics investigatory project
 
ASL/ALS CLASS 12 ENGLISH PROJECT
ASL/ALS CLASS 12 ENGLISH PROJECTASL/ALS CLASS 12 ENGLISH PROJECT
ASL/ALS CLASS 12 ENGLISH PROJECT
 
“To estimate the charge induced on each one of the two identical Styrofoam (o...
“To estimate the charge induced on each one of the two identical Styrofoam (o...“To estimate the charge induced on each one of the two identical Styrofoam (o...
“To estimate the charge induced on each one of the two identical Styrofoam (o...
 
Physics investigatory project class 12th.pdf
Physics investigatory project class 12th.pdfPhysics investigatory project class 12th.pdf
Physics investigatory project class 12th.pdf
 
Physics Practical File - with Readings | Class 12 CBSE
Physics Practical File - with Readings | Class 12 CBSEPhysics Practical File - with Readings | Class 12 CBSE
Physics Practical File - with Readings | Class 12 CBSE
 
Sterlization of water using bleaching powder
Sterlization of water using bleaching powder Sterlization of water using bleaching powder
Sterlization of water using bleaching powder
 

Viewers also liked

Physics investigatory project on RECTIFIER
Physics investigatory project on RECTIFIERPhysics investigatory project on RECTIFIER
Physics investigatory project on RECTIFIERNaveen R
 
Transformers Project report
Transformers Project reportTransformers Project report
Transformers Project reportTanuj Gupta
 
Logic gate class 12
Logic gate class 12Logic gate class 12
Logic gate class 12Nipun Shah
 
physics investigatory project class 12 on logic gates ,boolean algebra
physics investigatory project class 12 on logic gates ,boolean algebraphysics investigatory project class 12 on logic gates ,boolean algebra
physics investigatory project class 12 on logic gates ,boolean algebrasukhtej
 
12th CBSE Physics Project AC Generator
12th CBSE Physics Project AC Generator12th CBSE Physics Project AC Generator
12th CBSE Physics Project AC GeneratorAshwin Francis
 
Study The Presence of Oxalate Ions in Different Stages Of Guava
Study The Presence of Oxalate Ions in Different Stages Of GuavaStudy The Presence of Oxalate Ions in Different Stages Of Guava
Study The Presence of Oxalate Ions in Different Stages Of GuavaAman Sinha
 
A. c. generator by sujay class 12th
A. c. generator by sujay class 12thA. c. generator by sujay class 12th
A. c. generator by sujay class 12thSujay Lal
 
Physics Investigatory Project
Physics Investigatory ProjectPhysics Investigatory Project
Physics Investigatory ProjectNishant Jha
 
Physics investigatory project on Ohm's Law
Physics investigatory project on Ohm's LawPhysics investigatory project on Ohm's Law
Physics investigatory project on Ohm's LawPrakhar Seth
 
2017-18 ECONOMICS - CBSE SYLLABUS & PROJECT
2017-18 ECONOMICS - CBSE SYLLABUS & PROJECT 2017-18 ECONOMICS - CBSE SYLLABUS & PROJECT
2017-18 ECONOMICS - CBSE SYLLABUS & PROJECT CS. Sohil Gajjar
 
Physics project file on emi
Physics project file on emiPhysics project file on emi
Physics project file on emiAditya Sharma
 
Microbes in human welfare
Microbes in human welfareMicrobes in human welfare
Microbes in human welfareRahul Reghu
 
Total internal reflection optical fibre
Total internal reflection optical fibreTotal internal reflection optical fibre
Total internal reflection optical fibreelainesong716
 
EEE Introduction to Capacitors and Charging and Discharging of capacitors.
EEE  Introduction to Capacitors and Charging and Discharging of capacitors.EEE  Introduction to Capacitors and Charging and Discharging of capacitors.
EEE Introduction to Capacitors and Charging and Discharging of capacitors.Sukhvinder Singh
 
FIRE ALARM PHYSICS PROJECT CBSE CLASS 12
FIRE ALARM PHYSICS PROJECT CBSE CLASS 12FIRE ALARM PHYSICS PROJECT CBSE CLASS 12
FIRE ALARM PHYSICS PROJECT CBSE CLASS 12NIKHIL DUGGAL
 

Viewers also liked (20)

Physics project class 12 EMI
Physics project class 12 EMIPhysics project class 12 EMI
Physics project class 12 EMI
 
Physics investigatory project on RECTIFIER
Physics investigatory project on RECTIFIERPhysics investigatory project on RECTIFIER
Physics investigatory project on RECTIFIER
 
physics project
physics projectphysics project
physics project
 
Transformers Project report
Transformers Project reportTransformers Project report
Transformers Project report
 
Logic gate class 12
Logic gate class 12Logic gate class 12
Logic gate class 12
 
physics investigatory project class 12 on logic gates ,boolean algebra
physics investigatory project class 12 on logic gates ,boolean algebraphysics investigatory project class 12 on logic gates ,boolean algebra
physics investigatory project class 12 on logic gates ,boolean algebra
 
Physics investigatory project
Physics investigatory projectPhysics investigatory project
Physics investigatory project
 
12th CBSE Physics Project AC Generator
12th CBSE Physics Project AC Generator12th CBSE Physics Project AC Generator
12th CBSE Physics Project AC Generator
 
Study The Presence of Oxalate Ions in Different Stages Of Guava
Study The Presence of Oxalate Ions in Different Stages Of GuavaStudy The Presence of Oxalate Ions in Different Stages Of Guava
Study The Presence of Oxalate Ions in Different Stages Of Guava
 
A. c. generator by sujay class 12th
A. c. generator by sujay class 12thA. c. generator by sujay class 12th
A. c. generator by sujay class 12th
 
Physics Investigatory Project
Physics Investigatory ProjectPhysics Investigatory Project
Physics Investigatory Project
 
Physics investigatory project on Ohm's Law
Physics investigatory project on Ohm's LawPhysics investigatory project on Ohm's Law
Physics investigatory project on Ohm's Law
 
2017-18 ECONOMICS - CBSE SYLLABUS & PROJECT
2017-18 ECONOMICS - CBSE SYLLABUS & PROJECT 2017-18 ECONOMICS - CBSE SYLLABUS & PROJECT
2017-18 ECONOMICS - CBSE SYLLABUS & PROJECT
 
Telescope
TelescopeTelescope
Telescope
 
Physics project file on emi
Physics project file on emiPhysics project file on emi
Physics project file on emi
 
Phy1
Phy1Phy1
Phy1
 
Microbes in human welfare
Microbes in human welfareMicrobes in human welfare
Microbes in human welfare
 
Total internal reflection optical fibre
Total internal reflection optical fibreTotal internal reflection optical fibre
Total internal reflection optical fibre
 
EEE Introduction to Capacitors and Charging and Discharging of capacitors.
EEE  Introduction to Capacitors and Charging and Discharging of capacitors.EEE  Introduction to Capacitors and Charging and Discharging of capacitors.
EEE Introduction to Capacitors and Charging and Discharging of capacitors.
 
FIRE ALARM PHYSICS PROJECT CBSE CLASS 12
FIRE ALARM PHYSICS PROJECT CBSE CLASS 12FIRE ALARM PHYSICS PROJECT CBSE CLASS 12
FIRE ALARM PHYSICS PROJECT CBSE CLASS 12
 

Similar to Physics Investigatory Project Class 12

Physics investigatory
Physics investigatoryPhysics investigatory
Physics investigatoryHemant Singh
 
Physicsinv 140316012232-phpapp02 (1)
Physicsinv 140316012232-phpapp02 (1)Physicsinv 140316012232-phpapp02 (1)
Physicsinv 140316012232-phpapp02 (1)Supriya Td
 
physics investrigatory project
physics investrigatory projectphysics investrigatory project
physics investrigatory projectsuyash jagtap
 
transistor as a switch
transistor as a switchtransistor as a switch
transistor as a switchSahil Patel
 
XII INVESTIGATORY PHYSICS PROJECT
XII INVESTIGATORY PHYSICS PROJECTXII INVESTIGATORY PHYSICS PROJECT
XII INVESTIGATORY PHYSICS PROJECTEr Shambhu Chauhan
 
ISHA GOYAL 12THB PPT POWERPOINT.pptx
ISHA  GOYAL 12THB PPT POWERPOINT.pptxISHA  GOYAL 12THB PPT POWERPOINT.pptx
ISHA GOYAL 12THB PPT POWERPOINT.pptxIshaGoyal84
 
bblproject-12a-220703063018-87204256.pdf
bblproject-12a-220703063018-87204256.pdfbblproject-12a-220703063018-87204256.pdf
bblproject-12a-220703063018-87204256.pdfsiddhantkhurdiya
 
physics cbse 12th classs investigatory project
physics cbse 12th classs investigatory projectphysics cbse 12th classs investigatory project
physics cbse 12th classs investigatory projectVishvjeet Yadav
 
Physics investigatory project by pinaki bandyopadhyay
Physics investigatory project by pinaki bandyopadhyayPhysics investigatory project by pinaki bandyopadhyay
Physics investigatory project by pinaki bandyopadhyayPinaki Bandyopadhyay
 
kupdf.net_physics-project-on-quottransformersquot - Copy.pdf
kupdf.net_physics-project-on-quottransformersquot - Copy.pdfkupdf.net_physics-project-on-quottransformersquot - Copy.pdf
kupdf.net_physics-project-on-quottransformersquot - Copy.pdfPatelRushabh9
 
Physics investigatory project
Physics investigatory projectPhysics investigatory project
Physics investigatory projectShivalik school
 

Similar to Physics Investigatory Project Class 12 (20)

Physics investigatory
Physics investigatoryPhysics investigatory
Physics investigatory
 
Physicsinv 140316012232-phpapp02 (1)
Physicsinv 140316012232-phpapp02 (1)Physicsinv 140316012232-phpapp02 (1)
Physicsinv 140316012232-phpapp02 (1)
 
Physics investigatory
Physics investigatoryPhysics investigatory
Physics investigatory
 
Sanjay
SanjaySanjay
Sanjay
 
Physicstrans
PhysicstransPhysicstrans
Physicstrans
 
physics investrigatory project
physics investrigatory projectphysics investrigatory project
physics investrigatory project
 
Transformer
TransformerTransformer
Transformer
 
transistor as a switch
transistor as a switchtransistor as a switch
transistor as a switch
 
Physics Project
Physics ProjectPhysics Project
Physics Project
 
XII INVESTIGATORY PHYSICS PROJECT
XII INVESTIGATORY PHYSICS PROJECTXII INVESTIGATORY PHYSICS PROJECT
XII INVESTIGATORY PHYSICS PROJECT
 
ISHA GOYAL 12THB PPT POWERPOINT.pptx
ISHA  GOYAL 12THB PPT POWERPOINT.pptxISHA  GOYAL 12THB PPT POWERPOINT.pptx
ISHA GOYAL 12THB PPT POWERPOINT.pptx
 
bblproject-12a-220703063018-87204256.pdf
bblproject-12a-220703063018-87204256.pdfbblproject-12a-220703063018-87204256.pdf
bblproject-12a-220703063018-87204256.pdf
 
Transformers
TransformersTransformers
Transformers
 
physics cbse 12th classs investigatory project
physics cbse 12th classs investigatory projectphysics cbse 12th classs investigatory project
physics cbse 12th classs investigatory project
 
Pranav Shukla
Pranav ShuklaPranav Shukla
Pranav Shukla
 
Transformer
TransformerTransformer
Transformer
 
Physics investigatory project by pinaki bandyopadhyay
Physics investigatory project by pinaki bandyopadhyayPhysics investigatory project by pinaki bandyopadhyay
Physics investigatory project by pinaki bandyopadhyay
 
kupdf.net_physics-project-on-quottransformersquot - Copy.pdf
kupdf.net_physics-project-on-quottransformersquot - Copy.pdfkupdf.net_physics-project-on-quottransformersquot - Copy.pdf
kupdf.net_physics-project-on-quottransformersquot - Copy.pdf
 
Physics investigatory project
Physics investigatory projectPhysics investigatory project
Physics investigatory project
 
Step down transformer
Step down transformerStep down transformer
Step down transformer
 

More from Self-employed

Computer Science Investigatory Project Class 12
Computer Science Investigatory Project Class 12Computer Science Investigatory Project Class 12
Computer Science Investigatory Project Class 12Self-employed
 
Chemistry Investigatory Project Class 12
Chemistry Investigatory Project Class 12Chemistry Investigatory Project Class 12
Chemistry Investigatory Project Class 12Self-employed
 
Communication - Laser Class 12 Part-7
Communication - Laser Class 12 Part-7Communication - Laser Class 12 Part-7
Communication - Laser Class 12 Part-7Self-employed
 
Communication - Line Communication Class 12 Part-6
Communication - Line Communication Class 12 Part-6Communication - Line Communication Class 12 Part-6
Communication - Line Communication Class 12 Part-6Self-employed
 
Communication - Amplitude Modulation Class 12 Part-1
Communication - Amplitude Modulation Class 12 Part-1Communication - Amplitude Modulation Class 12 Part-1
Communication - Amplitude Modulation Class 12 Part-1Self-employed
 
Communication - Space Communication Class 12 Part-5
Communication - Space Communication Class 12 Part-5Communication - Space Communication Class 12 Part-5
Communication - Space Communication Class 12 Part-5Self-employed
 
Semiconductor Devices Class 12 Part-3
Semiconductor Devices Class 12 Part-3Semiconductor Devices Class 12 Part-3
Semiconductor Devices Class 12 Part-3Self-employed
 
Semiconductor Devices Class 12 Part-2
Semiconductor Devices Class 12 Part-2Semiconductor Devices Class 12 Part-2
Semiconductor Devices Class 12 Part-2Self-employed
 
Semiconductor Devices Class 12 Part-1
Semiconductor Devices Class 12 Part-1Semiconductor Devices Class 12 Part-1
Semiconductor Devices Class 12 Part-1Self-employed
 
Semiconductor Devices Class 12 Part-4
Semiconductor Devices Class 12 Part-4Semiconductor Devices Class 12 Part-4
Semiconductor Devices Class 12 Part-4Self-employed
 
Nuclei And Atoms Class 12
Nuclei And Atoms Class 12Nuclei And Atoms Class 12
Nuclei And Atoms Class 12Self-employed
 
Photoelectric Effect And Dual Nature Of Matter And Radiation Class 12
Photoelectric Effect And Dual Nature Of Matter And Radiation Class 12Photoelectric Effect And Dual Nature Of Matter And Radiation Class 12
Photoelectric Effect And Dual Nature Of Matter And Radiation Class 12Self-employed
 
Wave Optics Class 12 Part-1
Wave Optics Class 12 Part-1Wave Optics Class 12 Part-1
Wave Optics Class 12 Part-1Self-employed
 
Ray Optics Class 12 Part-2
Ray Optics Class 12 Part-2Ray Optics Class 12 Part-2
Ray Optics Class 12 Part-2Self-employed
 
Ray Optics Class 12 Part-1
Ray Optics Class 12 Part-1Ray Optics Class 12 Part-1
Ray Optics Class 12 Part-1Self-employed
 
Wave Optics Class 12 Part-2
Wave Optics Class 12 Part-2Wave Optics Class 12 Part-2
Wave Optics Class 12 Part-2Self-employed
 
Electromagnetic Waves Class 12
Electromagnetic Waves Class 12 Electromagnetic Waves Class 12
Electromagnetic Waves Class 12 Self-employed
 
Electromagnetic Induction Class 12
Electromagnetic Induction Class 12 Electromagnetic Induction Class 12
Electromagnetic Induction Class 12 Self-employed
 
Alternating Currents Class 12
Alternating Currents Class 12Alternating Currents Class 12
Alternating Currents Class 12Self-employed
 

More from Self-employed (20)

Computer Science Investigatory Project Class 12
Computer Science Investigatory Project Class 12Computer Science Investigatory Project Class 12
Computer Science Investigatory Project Class 12
 
Chemistry Investigatory Project Class 12
Chemistry Investigatory Project Class 12Chemistry Investigatory Project Class 12
Chemistry Investigatory Project Class 12
 
Communication - Laser Class 12 Part-7
Communication - Laser Class 12 Part-7Communication - Laser Class 12 Part-7
Communication - Laser Class 12 Part-7
 
Communication - Line Communication Class 12 Part-6
Communication - Line Communication Class 12 Part-6Communication - Line Communication Class 12 Part-6
Communication - Line Communication Class 12 Part-6
 
Communication - Amplitude Modulation Class 12 Part-1
Communication - Amplitude Modulation Class 12 Part-1Communication - Amplitude Modulation Class 12 Part-1
Communication - Amplitude Modulation Class 12 Part-1
 
Communication - Space Communication Class 12 Part-5
Communication - Space Communication Class 12 Part-5Communication - Space Communication Class 12 Part-5
Communication - Space Communication Class 12 Part-5
 
Semiconductor Devices Class 12 Part-3
Semiconductor Devices Class 12 Part-3Semiconductor Devices Class 12 Part-3
Semiconductor Devices Class 12 Part-3
 
Semiconductor Devices Class 12 Part-2
Semiconductor Devices Class 12 Part-2Semiconductor Devices Class 12 Part-2
Semiconductor Devices Class 12 Part-2
 
Semiconductor Devices Class 12 Part-1
Semiconductor Devices Class 12 Part-1Semiconductor Devices Class 12 Part-1
Semiconductor Devices Class 12 Part-1
 
Semiconductor Devices Class 12 Part-4
Semiconductor Devices Class 12 Part-4Semiconductor Devices Class 12 Part-4
Semiconductor Devices Class 12 Part-4
 
Nuclei And Atoms Class 12
Nuclei And Atoms Class 12Nuclei And Atoms Class 12
Nuclei And Atoms Class 12
 
Photoelectric Effect And Dual Nature Of Matter And Radiation Class 12
Photoelectric Effect And Dual Nature Of Matter And Radiation Class 12Photoelectric Effect And Dual Nature Of Matter And Radiation Class 12
Photoelectric Effect And Dual Nature Of Matter And Radiation Class 12
 
Wave Optics Class 12 Part-1
Wave Optics Class 12 Part-1Wave Optics Class 12 Part-1
Wave Optics Class 12 Part-1
 
Ray Optics Class 12 Part-2
Ray Optics Class 12 Part-2Ray Optics Class 12 Part-2
Ray Optics Class 12 Part-2
 
Ray Optics Class 12 Part-1
Ray Optics Class 12 Part-1Ray Optics Class 12 Part-1
Ray Optics Class 12 Part-1
 
Wave Optics Class 12 Part-2
Wave Optics Class 12 Part-2Wave Optics Class 12 Part-2
Wave Optics Class 12 Part-2
 
Electromagnetic Waves Class 12
Electromagnetic Waves Class 12 Electromagnetic Waves Class 12
Electromagnetic Waves Class 12
 
Electromagnetic Induction Class 12
Electromagnetic Induction Class 12 Electromagnetic Induction Class 12
Electromagnetic Induction Class 12
 
Alternating Currents Class 12
Alternating Currents Class 12Alternating Currents Class 12
Alternating Currents Class 12
 
Magnetism
MagnetismMagnetism
Magnetism
 

Recently uploaded

BÀI TẬP BỔ TRỢ TIẾNG ANH 11 THEO ĐƠN VỊ BÀI HỌC - CẢ NĂM - CÓ FILE NGHE (FRIE...
BÀI TẬP BỔ TRỢ TIẾNG ANH 11 THEO ĐƠN VỊ BÀI HỌC - CẢ NĂM - CÓ FILE NGHE (FRIE...BÀI TẬP BỔ TRỢ TIẾNG ANH 11 THEO ĐƠN VỊ BÀI HỌC - CẢ NĂM - CÓ FILE NGHE (FRIE...
BÀI TẬP BỔ TRỢ TIẾNG ANH 11 THEO ĐƠN VỊ BÀI HỌC - CẢ NĂM - CÓ FILE NGHE (FRIE...Nguyen Thanh Tu Collection
 
3.14.24 The Selma March and the Voting Rights Act.pptx
3.14.24 The Selma March and the Voting Rights Act.pptx3.14.24 The Selma March and the Voting Rights Act.pptx
3.14.24 The Selma March and the Voting Rights Act.pptxmary850239
 
Pharmacology chapter No 7 full notes.pdf
Pharmacology chapter No 7 full notes.pdfPharmacology chapter No 7 full notes.pdf
Pharmacology chapter No 7 full notes.pdfSumit Tiwari
 
30-de-thi-vao-lop-10-mon-tieng-anh-co-dap-an.doc
30-de-thi-vao-lop-10-mon-tieng-anh-co-dap-an.doc30-de-thi-vao-lop-10-mon-tieng-anh-co-dap-an.doc
30-de-thi-vao-lop-10-mon-tieng-anh-co-dap-an.docdieu18
 
3.12.24 The Social Construction of Gender.pptx
3.12.24 The Social Construction of Gender.pptx3.12.24 The Social Construction of Gender.pptx
3.12.24 The Social Construction of Gender.pptxmary850239
 
Material Remains as Source of Ancient Indian History & Culture.ppt
Material Remains as Source of Ancient Indian History & Culture.pptMaterial Remains as Source of Ancient Indian History & Culture.ppt
Material Remains as Source of Ancient Indian History & Culture.pptBanaras Hindu University
 
BBA 205 BUSINESS ENVIRONMENT UNIT I.pptx
BBA 205 BUSINESS ENVIRONMENT UNIT I.pptxBBA 205 BUSINESS ENVIRONMENT UNIT I.pptx
BBA 205 BUSINESS ENVIRONMENT UNIT I.pptxProf. Kanchan Kumari
 
POST ENCEPHALITIS case study Jitendra bhargav
POST ENCEPHALITIS case study  Jitendra bhargavPOST ENCEPHALITIS case study  Jitendra bhargav
POST ENCEPHALITIS case study Jitendra bhargavJitendra Bhargav
 
Research Methodology and Tips on Better Research
Research Methodology and Tips on Better ResearchResearch Methodology and Tips on Better Research
Research Methodology and Tips on Better ResearchRushdi Shams
 
DNA and RNA , Structure, Functions, Types, difference, Similarities, Protein ...
DNA and RNA , Structure, Functions, Types, difference, Similarities, Protein ...DNA and RNA , Structure, Functions, Types, difference, Similarities, Protein ...
DNA and RNA , Structure, Functions, Types, difference, Similarities, Protein ...AKSHAYMAGAR17
 
The basics of sentences session 8pptx.pptx
The basics of sentences session 8pptx.pptxThe basics of sentences session 8pptx.pptx
The basics of sentences session 8pptx.pptxheathfieldcps1
 
Quantitative research methodology and survey design
Quantitative research methodology and survey designQuantitative research methodology and survey design
Quantitative research methodology and survey designBalelaBoru
 
3.12.24 Freedom Summer in Mississippi.pptx
3.12.24 Freedom Summer in Mississippi.pptx3.12.24 Freedom Summer in Mississippi.pptx
3.12.24 Freedom Summer in Mississippi.pptxmary850239
 
LEAD6001 - Introduction to Advanced Stud
LEAD6001 - Introduction to Advanced StudLEAD6001 - Introduction to Advanced Stud
LEAD6001 - Introduction to Advanced StudDr. Bruce A. Johnson
 
The First National K12 TUG March 6 2024.pdf
The First National K12 TUG March 6 2024.pdfThe First National K12 TUG March 6 2024.pdf
The First National K12 TUG March 6 2024.pdfdogden2
 
25 CHUYÊN ĐỀ ÔN THI TỐT NGHIỆP THPT 2023 – BÀI TẬP PHÁT TRIỂN TỪ ĐỀ MINH HỌA...
25 CHUYÊN ĐỀ ÔN THI TỐT NGHIỆP THPT 2023 – BÀI TẬP PHÁT TRIỂN TỪ ĐỀ MINH HỌA...25 CHUYÊN ĐỀ ÔN THI TỐT NGHIỆP THPT 2023 – BÀI TẬP PHÁT TRIỂN TỪ ĐỀ MINH HỌA...
25 CHUYÊN ĐỀ ÔN THI TỐT NGHIỆP THPT 2023 – BÀI TẬP PHÁT TRIỂN TỪ ĐỀ MINH HỌA...Nguyen Thanh Tu Collection
 
Awards Presentation 2024 - March 12 2024
Awards Presentation 2024 - March 12 2024Awards Presentation 2024 - March 12 2024
Awards Presentation 2024 - March 12 2024bsellato
 

Recently uploaded (20)

BÀI TẬP BỔ TRỢ TIẾNG ANH 11 THEO ĐƠN VỊ BÀI HỌC - CẢ NĂM - CÓ FILE NGHE (FRIE...
BÀI TẬP BỔ TRỢ TIẾNG ANH 11 THEO ĐƠN VỊ BÀI HỌC - CẢ NĂM - CÓ FILE NGHE (FRIE...BÀI TẬP BỔ TRỢ TIẾNG ANH 11 THEO ĐƠN VỊ BÀI HỌC - CẢ NĂM - CÓ FILE NGHE (FRIE...
BÀI TẬP BỔ TRỢ TIẾNG ANH 11 THEO ĐƠN VỊ BÀI HỌC - CẢ NĂM - CÓ FILE NGHE (FRIE...
 
3.14.24 The Selma March and the Voting Rights Act.pptx
3.14.24 The Selma March and the Voting Rights Act.pptx3.14.24 The Selma March and the Voting Rights Act.pptx
3.14.24 The Selma March and the Voting Rights Act.pptx
 
Pharmacology chapter No 7 full notes.pdf
Pharmacology chapter No 7 full notes.pdfPharmacology chapter No 7 full notes.pdf
Pharmacology chapter No 7 full notes.pdf
 
t-test Parametric test Biostatics and Research Methodology
t-test Parametric test Biostatics and Research Methodologyt-test Parametric test Biostatics and Research Methodology
t-test Parametric test Biostatics and Research Methodology
 
30-de-thi-vao-lop-10-mon-tieng-anh-co-dap-an.doc
30-de-thi-vao-lop-10-mon-tieng-anh-co-dap-an.doc30-de-thi-vao-lop-10-mon-tieng-anh-co-dap-an.doc
30-de-thi-vao-lop-10-mon-tieng-anh-co-dap-an.doc
 
3.12.24 The Social Construction of Gender.pptx
3.12.24 The Social Construction of Gender.pptx3.12.24 The Social Construction of Gender.pptx
3.12.24 The Social Construction of Gender.pptx
 
Material Remains as Source of Ancient Indian History & Culture.ppt
Material Remains as Source of Ancient Indian History & Culture.pptMaterial Remains as Source of Ancient Indian History & Culture.ppt
Material Remains as Source of Ancient Indian History & Culture.ppt
 
BBA 205 BUSINESS ENVIRONMENT UNIT I.pptx
BBA 205 BUSINESS ENVIRONMENT UNIT I.pptxBBA 205 BUSINESS ENVIRONMENT UNIT I.pptx
BBA 205 BUSINESS ENVIRONMENT UNIT I.pptx
 
POST ENCEPHALITIS case study Jitendra bhargav
POST ENCEPHALITIS case study  Jitendra bhargavPOST ENCEPHALITIS case study  Jitendra bhargav
POST ENCEPHALITIS case study Jitendra bhargav
 
Research Methodology and Tips on Better Research
Research Methodology and Tips on Better ResearchResearch Methodology and Tips on Better Research
Research Methodology and Tips on Better Research
 
Least Significance Difference:Biostatics and Research Methodology
Least Significance Difference:Biostatics and Research MethodologyLeast Significance Difference:Biostatics and Research Methodology
Least Significance Difference:Biostatics and Research Methodology
 
DNA and RNA , Structure, Functions, Types, difference, Similarities, Protein ...
DNA and RNA , Structure, Functions, Types, difference, Similarities, Protein ...DNA and RNA , Structure, Functions, Types, difference, Similarities, Protein ...
DNA and RNA , Structure, Functions, Types, difference, Similarities, Protein ...
 
ANOVA Parametric test: Biostatics and Research Methodology
ANOVA Parametric test: Biostatics and Research MethodologyANOVA Parametric test: Biostatics and Research Methodology
ANOVA Parametric test: Biostatics and Research Methodology
 
The basics of sentences session 8pptx.pptx
The basics of sentences session 8pptx.pptxThe basics of sentences session 8pptx.pptx
The basics of sentences session 8pptx.pptx
 
Quantitative research methodology and survey design
Quantitative research methodology and survey designQuantitative research methodology and survey design
Quantitative research methodology and survey design
 
3.12.24 Freedom Summer in Mississippi.pptx
3.12.24 Freedom Summer in Mississippi.pptx3.12.24 Freedom Summer in Mississippi.pptx
3.12.24 Freedom Summer in Mississippi.pptx
 
LEAD6001 - Introduction to Advanced Stud
LEAD6001 - Introduction to Advanced StudLEAD6001 - Introduction to Advanced Stud
LEAD6001 - Introduction to Advanced Stud
 
The First National K12 TUG March 6 2024.pdf
The First National K12 TUG March 6 2024.pdfThe First National K12 TUG March 6 2024.pdf
The First National K12 TUG March 6 2024.pdf
 
25 CHUYÊN ĐỀ ÔN THI TỐT NGHIỆP THPT 2023 – BÀI TẬP PHÁT TRIỂN TỪ ĐỀ MINH HỌA...
25 CHUYÊN ĐỀ ÔN THI TỐT NGHIỆP THPT 2023 – BÀI TẬP PHÁT TRIỂN TỪ ĐỀ MINH HỌA...25 CHUYÊN ĐỀ ÔN THI TỐT NGHIỆP THPT 2023 – BÀI TẬP PHÁT TRIỂN TỪ ĐỀ MINH HỌA...
25 CHUYÊN ĐỀ ÔN THI TỐT NGHIỆP THPT 2023 – BÀI TẬP PHÁT TRIỂN TỪ ĐỀ MINH HỌA...
 
Awards Presentation 2024 - March 12 2024
Awards Presentation 2024 - March 12 2024Awards Presentation 2024 - March 12 2024
Awards Presentation 2024 - March 12 2024
 

Physics Investigatory Project Class 12

  • 2. KENDRIYA VIDYALAYA NO. 2 NAUSENABAUGH, VISAKHAPATNAM DEPARTMENT OF PHYSICS CERTIFICATE This is to certify that RAHUL KUSHWAHA, a student of class XII-A has successfully completed the research on the below mentioned project under the guidance of MR. RAMNA RAO ( Subject Teacher ) during the year 2013-14 in partial fulfillment of physics practical examination conducted by AISSCE, New Delhi. Signature of external examiner Signature of physics teacher
  • 3. ACKNOWLEDGEMENT In the accomplishment of this project successfully, many people have best owned upon me their blessings and the heart pledged support, this time I am utilizing to thank all the people who have been concerned with project. Primarily I would thank god for being able to complete this project with success. Then I would like to thank my principal Mr. S.V.Babu and physics teacher Mr.Ramna Rao, whose valuable guidance has been the ones that helped me patch this project and make it full proof success his suggestions and his instructions has served as the major contributor towards the completion of the project. Then I would like to thank my parents and friends who have helped me with their valuable suggestions and guidance has been helpful in various phases of the completion of the project. Last but not the least I would like to thank my classmates who have helped me a lot.
  • 4. INDEX 1.CERTIFICATE OF EXCELLENCE 2. ACKNOWLEDGEMENT 3. AIM OF PROJECT 4. INTRODUCTION 5. THEORY 6. APPARATUS REQUIRED 7. PROCEDURE FOLLOWED 8. OBSERVATION 9. CONCLUSION 10. PRECAUTION 11. BIBLIOGRAPHY
  • 5. INTRODUCTION The transformer is a device used for converting a low alternating voltage to a high alternating voltage or vice-versa. A Transformer based on the Principle of mutual induction according to this principle, the amount of magnetic flux linked with a coil changing, an e.m.f is induced in the neighboring coil. A transformer is an electrical device which is used for changing the A.C. voltages. A transformer is most widely used device in both low and high current circuit. As such transformers are built in an amazing strength of sizes. In electronic, measurement and control circuits, transformer size may be so small that it weight only a few tens of grams where as in high voltage power circuits, it may weight hundred of tones. In a transformer, the electrical energy transfer from one circuit to another circuit takes place without the use of moving parts. A transformer which increases the voltages is called a step- up transformer. A transformer which decreases the A.C. voltages is called a step-down transformer. Transformer is, therefore, an essential piece of apparatus both for high and low current circuits. OBJECTIVE To investigate the relation between the ratio of – 1. Input and output voltage. 2. Number of turnings in the secondary coil and primary coil of a self made transformer.
  • 6. When an altering e.m.f. is supplied to the primary coil p1p2, an alternating current starts falling in it. The altering current in the primary produces a changing magnetic flux, which induces altering voltage in the primary as well as in the secondary. In a good- transformer, whole of the magnetic flux linked with primary is also linked with the secondary, and then the induced e.m.f. induced in each turn of the secondary is equal to that induced in each turn of the primary. Thus if Ep and Es be the instantaneous values of the e.m.f.’s induced in the primary and the secondary and Np and Ns are the no. of turns of the primary secondary coils of the transformer and dф / dt = rate of change of flux in each turnoff the coil at this instant, we have Ep = -Np dф/dt _______________ (1) and Es = -Ns dф/dt _______________ (2) Since the above relations are true at every instant, so by dividing 2 by 1, we get Es / Ep = - Ns / Np ______________ (3)
  • 7. As Ep is the instantaneous value of back e.m.f induced in the primary coil p1, so the instantaneous current in primary coil is due to the difference (E – Ep ) in the instantaneous values of the applied and back e.m.f. further if Rp is the resistance o, p1p2 coil, then the instantaneous current Ip in the primary coil is given by Ip = E – Ep / Rp E – Ep = Ip Rp When the resistance of the primary is small, Rp Ip can be neglected so therefore E – Ep = 0 or Ep = E Thus back e.m.f = input e.m.f Hence equation 3 can be written as Es / Ep = Es / E = output e.m.f / input e.m.f = Ns / Np = K Where K is constant, called turn or transformation ratio.
  • 8. IN A STEP-DOWN TRANSFORMER Es < E so K < 1, hence Ns < Np If Ip = value of primary current at the same instant And Is = value of secondary current at this instant, then Input power at the instant = Ep Ip and Output power at the same instant = Es Is If there are no losses of power in the transformer, then Input power = output power Or Ep Ip = Es Is Or Es / Ep = Ip / Is = K
  • 9. IN A STEP-UP TRANSFORMER Es > E so K > 1, hence Ns > Np As, k > 1, so Ip > Is or Is < Ip i.e. current in secondary is weaker when secondary voltage is higher. Hence, whatever we gain in voltage, we lose in current in the same ratio. Similarly it can be shown, that in a step down transformer, whatever we lose in voltage, we gain in current in the same ratio. Thus a step up transformer in reality steps down the current & a step down transformer steps up the current.
  • 10. EFFICIENCY Efficiency of a transformer is defined as the ratio of output power to the input power. i.e. η = output power / input power = Es Is / Ep Ip Thus in an ideal transformer, where there is no power losses, η = 1. But in actual practice, there are many power losses; therefore the efficiency of transformer is less than one. ENERGY LOSSES Following are the major sources of energy loss in a transformer: 1. Copper loss is the energy loss in the form of heat in the copper coils of a transformer. This is due to joule heating of conducting wires. 2. Iron loss is the energy loss in the form of heat in the iron core of the transformer. This is due to formation of eddy currents in iron core. It is minimized by taking laminated cores.
  • 11. 3. Leakage of magnetic flux occurs inspite of best insulations. Therefore, rate of change of magnetic flux linked with each turn of S1S2 is less than the rate of change of magnetic flux linked with each turn of P1P2. 4. Hysteresis loss is the loss of energy due to repeated magnetization and demagnetization of the iron core when A.C. is fed to it. 5. Magneto striation i.e. humming noise of a transformer. APPARATUS REQUIRED IRON ROD COPPER WIRE VOLTMETER AMMETER
  • 12. CIRCUIT DIAGRAM PROCEDURE 1. Take thick iron rod and cover it with a thick paper and wind a large number of turns of thin Cu wire on thick paper (say 60). This constitutes primary coil of the transformer.
  • 13. 2. Cover the primary coil with a sheet of paper and wound relatively smaller number of turns (say 20) of thick copper wire on it. This constitutes the secondary coil. It is a step down transformer. 3. Connect p1, p2 to A.C main and measure the input voltage and current using A.C voltmeter and ammeter respectively. 4. Similarly, measure the output voltage and current through s1and s2. 5. Now connect s1and s2to A.C main and again measure voltage and current through primary and secondary coil of step up transformer. 6. Repeat all steps for other self made transformers by changing number of turns in primary and secondary coil. USES OF TRANSFORMER A transformer is used in almost all a.c. operations- In voltage regulator for T.V., refrigerator, computer, air conditioner, etc.  A step down transformer is used for welding purposes.  A step down transformer is used for obtaining large current.  A step up transformer is used for the production of X-Rays and NEON advertisement.  Transformers are used in voltage regulators and stabilized power supplies.  Transformers are used in the transmissions of a.c. over long distances. Small transformers are used in Radio sets, telephones, loud speakers and electric bells etc
  • 14. SOURCES OF ERROR 1. Values of current can be changed due to heating effect. 2. Eddy current can change the readings. 1. The output voltage of the transformer across the secondary coil depends upon the ratio (Ns/Np) with respect to the input voltage 2. The output voltage of the transformer across the secondary coil depends upon the ratio (Ns/N p) with respect to the input voltage 3. There is a loss of power between input and output coil of a transformer. ________________________________________________________________________ ________________________________________________________________________ PRECAUTIONS 1. Keep safe yourself from high voltage. 2. While taking the readings of current and voltage the A.C should remain constant. CONCLUSION
  • 15. 1) NCERT textbook class 12 2) NCERT physics lab Manuel 3) INTERNET 4) www.yahoo.com 5) www.scribd.com 6) www.google.com BIBLIOGRAPHY HELP FROM INTERNET INFORMATION FROM LIBRARY HELP FROM TEACHERS