This document summarizes a physics student's cell charger project. It includes an acknowledgement of those who helped and supported the project, a brief introduction describing the components used including a step down transformer, diodes, LED and resistor. It then explains the working of the circuit, showing how AC power is transformed to DC using the transformer and rectifier to charge a cell. A circuit diagram and list of precautions in building the circuit are also provided. References used in completing the project are cited.

1. PHYSICS PROJECT
CELL CHARGER
A Project Submitted to
Department of Physics
For the fulfillment of the Requirement
Of Practical Exam
OfAISSCE-2016
BY
UNDER SUPERVISION OF
Dr. S.K . MISHRA
GAURAV KUMAR
Roll No. 5641698

2. 1
I thank my Physicsteacher Dr. S.K. Mishrafor
guidance, supportand suggesting the project“CELL
CHARGER”.
I would also like to thank my parents and my
friends for encouraging me during the course of this
project.
Finally I would like to thank CBSEfor giving
me thisopportunity to undertake thisproject.
THANK YOU,
GAURAVKUMAR
ACKNOWLEDGEMENT

3. 2
Often it is seen that when we want to on the radio or
Walkman to listen a song then our cell becomes weak.
At this time cell charger helps us. It will charge the cell
and save our money twice or thrice.
NOTE:- This model is used only when the cell is not
fully weak.
Introduction

4. 3
1. STEP DOWN TRANSFORMER (6V)
2. p-n JUNCTION (4 DIODES)
3. LED (1)
4. RESISTANCE
5. CONNECTING WIRES
Componentsused

5. 4
STEP DOWN TRANSFORMER –
It is used for stepping down the voltage of 220V to a
particular voltage that is required for circuit operation.
RECTIFIER –
It convert the A.C into repelled D.C.
LED –
It is light emitting device used for indication of diode
and transistor service ability.
RESISTANCE –
It is the hindrance offered by positive ions due to
drifting electrons when a PD is applied on the end of
the conductor.
DESCRIPTION OFTHE COMPONENTS

6. 5
In the cell charger when main AC current is
supplied to the primary winding of the transformer
then due to mutual induction in the secondary winding
AC is produced. When one end of transformer’s
secondary winding is positive then the other end
becomes negative at the same time and vice-versa.
This AC is given to the rectifier circuit. Rectifier
converts the AC signal into repelled DC. Therefore we
will get 6V DC at the two points connected with a
battery. Finally in the battery we are supplying 6V
direct supply.
Working

7. 6
Circuit diagram

8. 7
1. Keep yourself safe from high voltage.
2. Solder the wire safely.
3. While soldering don’t touch the soldering tip.
4. Solder under adult supervision.
Precautions

9. 8
In completing this project I took the help from the
following –
1.NCERT Physics - Pg. no. – 220
6.9.3 Mutual induction
2.NCERT Physics - Pg. no. – 483
14.7 Rectifier
Bibliography