This document is a physics investigatory project report submitted by Tejas Jain to study the factors that affect the self-inductance of a coil. The aim is to observe how the effect of a coil changes when placed in series with a resistor (bulb) in a circuit powered by an AC source of adjustable frequency. The theory section explains that self-inductance is a property of current-carrying coils that opposes changes in current flow and is caused by the self-induced EMF produced in the coil. The factors that affect self-inductance are the number of turns, geometry of the coil, and nature of the core material. The procedure and observations sections are not included.

1. PHYSICS INVESTIGATORY
PROJECT
2023-24
NAME : TEJAS JAIN
Class : XII-A
TOPIC
To study the factors on which self inductance of cell depends by observing the effect of coil when
put in series with a resistor(bulb) in a circuit fed up by an A.C. source of adjustable frequency
Submitted to:-
Mr. Arvind aarya
Submitted by :-
Tejas jain

2. S.NO NAME PAGE NO. REMARKS
1. Certificate
2. Acknowledgement
3. Aim of project
4. Theory
5. Procedure
6. Observation
7. Result
8. Sources of errors
9. Precautions
10. Bibliography

3. CERTIFICATE
This is to certify that _________________________ a student of class __________ has
successfully completed the research on the topic “To study the factors on which self inductance
of cell depends by observing the effect of coil when put in series with a resistor(bulb) in a circuit
fed up by an A.C. source of adjustable frequency” under the guidance of __________________
during the year 2023-24 in partial fulfillment of physics practical examination of Central Board of
Secondary Education(CBSE).
________________ __________________
principal subject teacher
Presentation title 3

4. ACKNOWLEDGEMENT
I warmly acknowledge the continuous
encouragement offered by out principal
__________________. I extend my heartly thanks
for giving me the opportunity to make use of
the facilities around the school campus to carry
out the project.
I am highly indebted to __________________ for the
constand supervision,help and providing
information in the project.i would like to express
my gratitude towars him.
I am making this project for my knowledge

5. AIM
5
• To study the factors on which self inductance of cell
depends by observing the effect of coil when put in
series with a resistor(bulb) in a circuit fed up by an
A.C. source of adjustable frequency

6. SELF INDUCTANCE
“
Self-inductance is the property of the current-carrying coil that
resists or opposes the change of current flowing through it. This
occurs mainly due to the self-induced emf produced in the coil itself.
In simple terms, we can say that self-inductance is a phenomenon
where there is the induction of a voltage in a current-carrying wire
”
6

7. •When an electric current is passed through an
insulated conducting coil, it give rise to a
magnetic field in the coil so that the coil itself
behaves like a magnet
7
• The magnetic flux produced by the
current in the coil is linked with the
coil

8. DEFINATION
As the strength of the coil of the current in
the coil is changed,the flux linked with the
coil also changes.Under such
circumstances an emf is induced in the
coil too. Such emf is called self induced
emf and this phenomenon is called SELF
INDUCTANCE

10. Hence, the self inductance depends upon:
1. No. of turns (N), Lα N²
2. Geometry of coil, Lα A, L α(1/l)
3. Nature of core material, Lα µ
When an inductor is connected in series with a
resistor (bulb) with a variable source of frequency,
then current flowing in the bulb is
Irms = Erms/Z
Where, Z = √ R2 + ω2 = Impedance of the a.c.
circuit. Here
R = Resistance of the bulb
L = Self inductance of coil
ω = 2πf = Angular frequency of a.c. source

11. 11
• If the number of turn in a coil is N and
the flux linked with each turn is, then
the total flux linked through the coil =
No.
• In this case, the total flux linked with
the coil (which is called flux linkage) is
directly proportional to the current I
flowing through the coil.

12. Where the constant of proportionality
L is called the self inductance of coil
Nϕ = LI ; L = Nϕ/ I
The self inductance L is measure of flux
linked with the coil per unit current

13. • Form equation e = -L dI/dt
• Self inductance L = -e/(dI/dt)
• "The self-induced emf produced per unit rate of
change of current in the circuits called self-
inductance of the circuit."
• Unit of L unit of emf(v)/Unit of rate of change
of current (A/s)=Vs/A or Henry(H)

14. OBSERVATIONS
14

15. THANK YOU
Mirjam Nilsson​
mirjam@contoso.com
www.contoso.com