Physics Investigatory Project LIGHT DEPE
Physics Investigatory Project LIGHT DEPE
Physics Investigatory Project LIGHT DEPE
Submitted by
Gopi Nath Sah
Class XII A
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Acknowledgement
I would like to express my special thanks of
gratitude to my teacher (Mrs. Alka Chopra)
as well as our principal (R K Tyagi) who
gave me the golden opportunity to do this
wonderful project on the topic (Write the
topic name), which also helped me in doing
a lot of Research and i came to know about
so many new things I am really thankful to
them.
Secondly I would also like to thank my
parents and friends who helped me a lot in
finalizing this project within the limited time
frame.
Bonafide certificate
This is to certify that Gopi Nath Sah of class XII A has
successfully completed the investigatory project on
“TO STUDY VARIATION OF CURRENT USING A
LDR" under the guidance of Mrs. Alka Chopra .This
project is absolutely genuine and doesn't not involve in
any kind of plagiarism. This is in partial fulfillment of
Physics practical examination CBSE 2016.
Department of Physics
(Mrs Alka Chopra)
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INDEX
ACKNOWLEDGEMENT
i.
BONAFIDE CERTIFICATE
ii.
1. INTRODUCTION
2
2. AIM & APPARATUS
3
3. PHOTORESISTOR DISCOVERY
4-5
AND MECHANISM
4. PRINCIPLE & THEORY
5-6
5. BRIEF DESCRIPTION OF
6-8
COMPONENTS
6. APPLICATIONS
9
7. PROCEDURE
10
8. OBSERVATIONS
11-14
9. RESULT & CONCLUSIONS
15
10. BIBLOGRAPHY
16
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APPARATUS:
Light Dependent Resistor(LDR),Connecting Wires, Source of
different power rating(bulbs), Bulb Holder , Metre scale, Multi
Meter Battery.
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Photoresistor mechanism
A photoresistor or photocell is a component that uses a
photoconductor between two contacts. When this is exposed to
light a change in resistance is noted. Photoconductivity - the
mechanism behind the photoresistor - results from the
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PRINCIPLE
This project is based on Light Dependent Resistance
(L.D.R.). Light Dependent Resistance [LDR] is a resistance, in
which opposing power of current depends on the presence of
quantity of light present, i.e. the resistance of LDR increases or
decreases, according to quantity of light which falls on it.
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USES
Photoresistor
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Applications
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PROCEDURE
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OBSERVATIONS :-
The experiment has been conducted by using various sources with
different power ratings. Voltage of the battery = 6 V.
OBSERVATIONS TABLE :-
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Distance
between Source(Bulb)
S.No. LDR and Of power Resistance(Ω ) Current(mA)
the source imputs(W)
d(cm)
1. 10 15 1310 4.58
2. 10 30 770 7.00
3. 10 60 285 21.00
4. 10 100 195 30.00
1. 20 15 2800 2.14
2. 20 60 650 9.00
3. 20 100 435 13.79
1. 30 15 4300 1.4
2. 30 60 1000 6.00
3. 30 100 660 9.00
Distance between
S.No. LDR and the Resistance(Ω ) Current(µA)
source d(cm)
1. 4 1010 5.94
2. 6 1350 4.44
3. 8 1490 4.03
4. 10 1610 3.73
5. 12 1740 3.45
6. 14 1880 3.19
7. 16 2300 2.61
8. 18 2540 2.36
9. 20 2800 2.14
10. 22 3000 2.00
11. 24 3240 1.85
Distance between
S.No. LDR and the Resistance(Ω ) Current(mA)
source d(cm)
1. 4 105 57
2. 6 180 33
3. 8 230 26
4. 10 280 21
5. 12 360 16
6. 14 440 13
7. 16 500 12
8. 18 575 10
9. 20 675 8.8
10. 22 740 8.1
11. 24 820 7.3
Distance between
S.No. LDR and the Resistance(Ω ) Current(mA)
source d(cm)
1. 4 80 75
2. 6 130 46
3. 8 170 35
4. 10 205 29
5. 12 270 22
6. 14 300 20
7. 16 360 16
8. 18 410 14
9. 20 460 13
10. 22 525 11
11. 24 585 10
SOURCES OF ERROR
Biblography