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

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SUMMARY

Coulomb's law applies to "stationary charges," which means that the charges are not moving relative to each other and can be treated as static for the purposes of electrostatics. If charges are in motion, the full set of Maxwell's equations must be utilized to account for electric and magnetic fields. Observers moving at constant velocity can apply Coulomb's law, while those accelerating cannot. In many practical scenarios, the velocities involved are negligible, allowing for the effective use of electrostatics.

PREREQUISITES
  • Understanding of Coulomb's law
  • Familiarity with electrostatics
  • Basic knowledge of Maxwell's equations
  • Concept of reference frames in physics
NEXT STEPS
  • Study the implications of Maxwell's equations on moving charges
  • Explore the concept of reference frames in classical mechanics
  • Learn about the conditions under which electrostatics can be approximated
  • Investigate the effects of velocity on electric fields
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Introductory physics students, educators, and anyone seeking to understand the principles of electrostatics and the application of Coulomb's law in various reference frames.

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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