Kirchhoff’s Voltage Law
N
Naam
mee::
To investigate the distribution of electric potential in a series circuit.
There is an electric potential difference across any resistance
carrying an electric current. This potential difference is found by
using Ohm’s Law. The role of the battery in a circuit is to maintain a
constant potential difference between its terminals. In a circuit
containing several resistances, the electric potential difference is
distributed in a very definite way.
1. Using OhmZone construct the circuit illustrated in the diagram
below using the following materials:
• one battery
• 5 connecting wires
• 100 Ω resistor
• 20 Ω resistor
V3
20 Ω
100 Ω
V2
V1
2. Attach the voltmeter across the terminals of the battery and
across each of the two resistors. Record the following
information:
V1 =__________
V2 =__________
V3 =__________
Kirchhoff’s Voltage Law
1
By Janice Williams
3. Replace the 100 Ω resistor with another 20 Ω resistor. Once again,
record the voltmeter readings:
V1 =__________
V2 =__________
V3 =__________
4. Analyze your data, then establish a RULE to reflect your
observations. Notice that V1 is the potential difference across the
source (battery).
My rule describing electric potential difference in a series circuit:
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Justification
Gustav Robert
Kirchhoff
(1824-1887)
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Trial 1
Trial 2
5. In conclusion, relate your observations and results to Kirchhoff’s
Current Law for series circuits.
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____________________________________________________________
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Kirchhoff’s Voltage Law
2
By Janice Williams