Palestine Polytechnic University
College of Engineering
Department of Mechanical Engineering
Electrical Circuits Lab
Ohms law
Abed AL-Rahman Mohamed Mahmoud Dakdak
September 28, 2024
Under the supervision of Eng. Shehda Zahida
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Contents:
Summary………………………………………………………………….
1. Objective (Introduction)………………………………………………..
2. Methods………………………………………………………………...
3. Results………………………………………………………………….
4. Discussion……………………………………………………………...
5. Conclusion……………………………………………………………..
References………………………………………………………………...
Appendices………………………………………………………………..
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Summary:
The aim of this experiment is to calculate the current practically and theoretically
and what happens in the event of a change in resistance or voltage and the methods
that we do theoretically through Ohm's Law or practically by connecting the
correct circuit and then recording the results based on this experiment and
interpreting the results that appeared and then we deduce the relationships related
to the current through what we did.
1. Objective (Introduction):
We do this experiment in order to calculate the current and find the relationship
between the current and the resistance. When we increase or decrease the
resistance, as well as the potential difference, we learn how to calculate the electric
current practically and theoretically and find the relationships related to the electric
current.
2. Methods:
This stage can be divided into two parts:
The first theoretical stage:
In this stage, we calculate the current theoretically through Ohm's law and we only
change the value of the voltage difference and resistance and we calculate through
the following relationship:
V=I*R
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The second practical stage:
We connect the electrical circuit as shown in the picture and then we change the
voltage value 2-10 and record the readings and then we change the resistance value
and change the voltage value 2-10 and record the readings.
3. Results:
1. WHEN R= 15 OHM (EXP)
Vs = 2V 4V 6V 8V 10V
I= 110.8 mA 264 mA 402 mA 498 mA 498 mA
2. WHEN R= 15 OHM (TH)
Vs = 2V 4V 6V 8V 10V
I= 133.3 mA 266.6 mA 400 mA 533.3 mA 666.6 mA
3. WHEN R= 68 OHM (EXP)
Vs = 2V 4V 6V 8V 10V
I= 29.5 mA 57.3 mA 87.4 mA 118.8 mA 152.2 mA
4. WHEN R= 68 OHM (TH)
Vs = 2V 4V 6V 8V 10V
I= 29.4 mA 58.8 mA 88.2 mA 117.6 mA 147.05 mA
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4. Discussion:
In the case of 15 ohms:
All values between the practical and theoretical are very close except for the first
case (V = 2) due to taking the reading quickly and not waiting for the current to
complete and in the fifth case (V = 10) and the error in that is the burning of the
resistor and the resistance not being able to withstand the high current and thus the
reading is wrong.
In the case of 68 ohms:
All values are close and the reason for the slight error in the reading is the accuracy
and losses that occur in the devices and despite that the values are close.
5. Conclusion:
We made the results and discussion by comparing the practical and theoretical
values of the electric current through the change in the values of the potential
difference and the change in the resistance. Most of the results were close except
for two readings due to the error in not taking the necessary accuracy and the
second due to the burning of the resistance and its inability to withstand the high
current. Therefore, we can conclude that the larger the current, the greater the
resistance is required to withstand the current passing through it. Extreme accuracy
must be observed when performing such experiments.
References:
https://drive.google.com/file/d/1N6GNbz4GyeeTEzBBCnoRYmguYVXeyIux/vie
w
Appendices:
R = 2 OHM , V = 2V , I = ??
I = V/R , I = 2 / 2 , I = 1A
The end
Thanks
