Ignoring the sign of a charge in electromagnetism

AI Thread Summary
In electromagnetism, when calculating forces and potentials using Coulomb's law, the sign of the charge is crucial for determining the direction of the electric field and force. Ignoring the negative sign of a charge can lead to incorrect results, as seen in the discussion where a charge was mistakenly treated as positive, affecting the final answer's sign. The participant realized that the correct value for the potential should have included the negative sign for a negative charge. Understanding the implications of charge signs is essential for accurate calculations in electric fields. Proper attention to charge signs is necessary to ensure correct results in electromagnetism problems.
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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



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The Attempt at a Solution



Any insight into this will be greatly appreciated!
 
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