Measurement Errors in Kirchhoff's Voltage Law

AI Thread Summary
Measurement errors in Kirchhoff's Voltage Law can arise from procedural mistakes, such as incorrectly placing probes when measuring voltage across circuit elements. The discussion highlights that if two loops exhibit nearly opposite voltage sums, it may indicate a common source of error, possibly related to transcription mistakes in recorded measurements. The importance of careful measurement and recording practices is emphasized to avoid such discrepancies. Identifying and correcting these errors is crucial for accurate application of Kirchhoff's Laws. Proper attention to detail in experimental procedures can significantly improve the reliability of results.
Elliott Pryor
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Homework Statement


For a lab, we explored Kirchhoff's Laws. I made a procedural mistake while measuring my voltage values across my different elements. I know that all of my calculated voltage sums are correct, so I was wondering what I might have done to have loops ACBA and CDBC have almost perfectly opposite voltage sums?
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Homework Equations



Kirchhoff's Voltage Law: Around any closed loop the sum of the voltage changes is equal to zero.

The Attempt at a Solution



I have no idea. Maybe I placed one probe at point B (the end of the circuit) and measured the voltage difference between each element and the end instead of across the element.
 

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Elliott Pryor said:

Homework Statement


For a lab, we explored Kirchhoff's Laws. I made a procedural mistake while measuring my voltage values across my different elements. I know that all of my calculated voltage sums are correct, so I was wondering what I might have done to have loops ACBA and CDBC have almost perfectly opposite voltage sums?
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View attachment 223091

Homework Equations



Kirchhoff's Voltage Law: Around any closed loop the sum of the voltage changes is equal to zero.

The Attempt at a Solution



I have no idea. Maybe I placed one probe at point B (the end of the circuit) and measured the voltage difference between each element and the end instead of across the element.
Look for transcription errors in your recorded measurements (or you may have transcribed digits when you initially wrote down a measurement).
It may be significant that you have opposite errors of the same magnitude in two different loops. It suggests a common source for the error. What would be a common source of error for the two loops?
 
Last edited:
tnich said:
Look for transcription errors in your recorded measurements (or you may have transcribed digits when you initially wrote down a measurement).
It may be significant that you have opposite errors of the same magnitude in two different loops. It suggests a common source for the error. What would be a common source of error for the two loops?
Thank you! I never noticed!
 
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