Ignoring the sign of a charge in electromagnetism

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SUMMARY

The discussion centers on the importance of correctly accounting for the sign of charges in electromagnetism, specifically in the context of Coulomb's Law and electric field calculations. The user mistakenly used a positive charge value of 4μC instead of the correct negative value of -4μC, leading to an incorrect sign in their final answer. This highlights the necessity of considering charge signs when calculating electric potential and forces to ensure accurate results in electromagnetism problems.

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  • Understanding of Coulomb's Law
  • Knowledge of Electric Field Strength equations
  • Familiarity with Electric Potential concepts
  • Basic principles of charge interactions
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  • Study the derivation and application of Coulomb's Law
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Homework Statement



I just did a question on a charge moving relative to a stationary charge from an initial position x1 to a final position x2. I was under the impression that for questions involving coulombs law, and the equations for Electric Field Strength, Force and Potential we ignore any -ve signs on charges?

So after checking my answer I saw that I had the right magnitude but the wrong sign. The only thing I did differently was take the charge in my equation for the potential as 4μC instead of -4μC as can be seen on line 4 of the calculation below.

Homework Equations



wh1lv.png


The Attempt at a Solution



Any insight into this will be greatly appreciated!
 
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