Lab 3 Kirchoff

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Lab 3Kirchoffs Current and Voltage Laws
By Brad Peirson

• EGR 103
• Engineering Measurement and Analysis
• Section 4
• 4-14-04
• Instructor Dr. Marvel

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Purpose
Kirchoffs Laws are meant to calculate unknown
currents, voltages and resistances by generating
algebraic equations.
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The Circuit
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Voltage Law

• The voltage in a closed loop is equal to zero
• No closed loop can contain another closed loop

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Current Law

• The current leaving a node is equal to the
  current entering a node

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Apparatus
Circuit Design Trainer
Digital Multimeter
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Procedure

• The actual resistance and the voltage across each
  resistor was measured

Resistor Nominal Value Actual Value Voltage
R1 1.8 1.7 1.167
R2 3.0 2.9 1.965
R3 5.1 5.1 1.236
R4 4.3 4.2 1.876
R5 3.3 3.3 0.640
R6 6.8 6.7 0.640

Total Resistance 7.595
Voltage Source 5.000
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Procedure

• These values were inserted into the equations
  generated before to calculate theoretical values
  for the currents

Current Measured (mA) Theoretical (A) Discrepancy
R1 0.658 0.000688 4.6
R3 0.290 0.000251 13.4
R4 0.368 0.000437 18.7
R5 0.193 0.000168 12.9
R6 0.095 0.000083 12.8
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Conclusions

• Error relatively close
• Main error source is the same for all trials
• Kirchoffs Laws are true