What does "stationary charges" mean in Coulomb's law?

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In Coulomb's law, "stationary charges" refers to charges that do not move relative to each other, allowing for the application of electrostatics. If charges are in motion, the full set of Maxwell's equations is required to describe their behavior, as electrostatics no longer applies. An observer moving at a constant velocity with the charges can still apply Coulomb's law, while a stationary observer cannot. The discussion highlights that in many practical scenarios, the velocities involved may be negligible, making electrostatic approximations valid. Understanding these nuances is essential for accurately applying Coulomb's law in different contexts.
Amio C
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Hello. I am an intro Physics student and this is my first post here.

In Coulomb's law the charges are said to be stationary. I need some clarification about what does it mean for two charges to be stationary:

A. Does it mean that the charges are not moving with respect to each other? (But maybe can move together with a constant velocity?)
B. Does it mean that the charges and the observer applying Coulomb's law has no movement compared to each other?
C. What if the charges and the observer all are accelerating at the same rate?

I am sorry if the answer is obvious. I would really appreciate your help.
 
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B. If the charges move you are no longer dealing with electrostatics and you will need the full set of Maxwell's equations to describe the electric and magnetic fields.
 
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Orodruin said:
B. If the charges move you are no longer dealing with electrostatics and you will need the full set of Maxwell's equations to describe the electric and magnetic fields.
Thank you for your answer. Please help me a bit more.
So if two charges along with an observer (let's call him / her "X") is moving at a constant velocity and another observer ("Y") is not moving; then "X" can apply Coulomb's law but "Y" can not - am I correct?
 
Amio C said:
Thank you for your answer. Please help me a bit more.
So if two charges along with an observer (let's call him / her "X") is moving at a constant velocity and another observer ("Y") is not moving; then "X" can apply Coulomb's law but "Y" can not - am I correct?

Yes - and of course this situation is equivalent to X and the two charges being at rest while Y is moving.
 
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Thanks to both of you. I understand it now.
 
This being said, it should be noted that in many of the cases you might deal with, velocities will be so small that you can apply electrostatics to a very good approximation.
 
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