University of Bahrain
College of Applied Studies
EEA111 – Electrical Technology
E
xperiment 3
Series Resistanc and Kirchhoff’s voltage law
Objective:
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Equipment:
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Determine the total resistance of series and Parallel dc circuit using an
ohmmeter or an application of ohm's law
Calculate the total resistance of a series and Parallel dc circuit and note
the effect of the relative magnitude of each series and Parallel on the
total resistance
Learn to identify which resistors and Parallel of a network are in series
Determined the current in each circuit element
Determined the voltage in each circuit element
Resistors 100 Ω,220 Ω , 330 Ω , 1K Ω , 100K Ω
DC Power Supply
Malta meter
Theory
The total resistance Rt of a series circuit is the sum of the individual
resistances
For equal series resistors, the total resistance is equal to the resistance of one
resistor times the number in series
For any system , the total resistance can be determined by the following form of ohm's
law:
1
University of Bahrain
College of Applied Studies
EEA111 – Electrical Technology
That is for an applied voltage E the current is measured and is applied to determine
the resistance of the network
In a series circuit, the current is the same through the entire circuit element
By ohm's law, the current I is = E/RT, where E is the impressed voltage and Rt the
total Resistance
Kirchhoff’s voltage law states that around any closed Path in a n electric circuit , the
algebraic sum of all the voltage drops must equal the algebraic sum of all the voltage
rises , this means that that the sum of the voltage drops across the series resistors must
equal the voltage applied across the series resistance combination .therefore, using
Kirchhoff’ voltage law and ohms law
V = V1+V2+V3
Where V1= (I)(R1) , V2= (I)(R2),and V3= (I)(R3)
Part 1-1
Two Series Resistors
1- Construct the Circuit
R1 measured = _________
R2 measured = __________
2- Measure the total resistance RT measured =_________
3- Calculate the total resistance RT calculated=
4- How do the measured and calculated values
compare? Calculate the magnitude of the percent
difference from
measured − Calculated
× 100%
Calculated
_____________________________________________
% Difference =
2
University of Bahrain
College of Applied Studies
EEA111 – Electrical Technology
5- Set the Supply to 8 V , find the following
VR1
VR2
IS
Part 1-2
Three Series Resisteors
1- Construct the Circuit
R1 measured = _________
R2 measured = _________
R3 measured =_________
2- Measure the total resistance RT measured =_________
3- Calculate the total resistance RT calculated=
_____________________________________________
_____________________________________________
4- How do the measured and calculated values
compare? Calculate the magnitude of the percent
difference from
measured − Calculated
× 100%
Calculated
_____________________________________________
% Difference =
_______________________________________________
_______________________________________________
3
University of Bahrain
College of Applied Studies
EEA111 – Electrical Technology
5- Set the Supply to 8 V , find the following
IS
VR1
VR2
VR3
IS
Part 1-3
6- Using the supply voltage and ammeter reading from
step 5 , calculate the total resistance using Eq
_____________________________________________
A Composite
1- Construct the Circuit
R1 measured = _________
R2 measured = _________
R3 measured =_________
R4 measured =_________
R5 measured =_________
2- Measure the total resistance RT measured =_________
3- Calculate the total resistance RT calculated=
____________________________________________
4
University of Bahrain
College of Applied Studies
EEA111 – Electrical Technology
4- How do the measured and calculated values
compare? Calculate the magnitude of the percent
difference from
measured − Calculated
× 100%
Calculated
_______________________________________________
_______________________________________________
% Difference =
5- Set the Supply to 8 V , find the following
VR1
VR2
VR3
VR3
VR3
IS
Exercises
1. Which resistors of next figure are in series?
2. Given the voltage level of next figure , determine the total resistance
RT , of the system and the resistance of the container , RT , show all
calculations
5
University of Bahrain
College of Applied Studies
EEA111 – Electrical Technology
3. Given the information appearing in next figure , determine the
resistance R2
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