Newton's 3rd Law and electric charges

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SUMMARY

Newton's 3rd Law does not apply to electric charges in motion, particularly when dealing with identical positive charges moving perpendicular to each other. The magnetic forces exerted by these charges are equal in magnitude but differ in direction, indicating that the law fails to hold in this context. The momentum of the electromagnetic fields surrounding the charges alters, leading to a lack of conservation of mechanical momentum. This highlights the limitations of classical mechanics when applied to electromagnetic interactions.

PREREQUISITES
  • Understanding of Newton's Laws of Motion
  • Basic knowledge of electric charges and magnetic forces
  • Familiarity with electromagnetic field theory
  • Concept of momentum conservation in physics
NEXT STEPS
  • Study the implications of special relativity on electric charges
  • Explore the concept of electromagnetic fields and their momentum
  • Learn about the Lorentz force and its effects on charged particles
  • Investigate the differences between classical and quantum mechanics in relation to charge interactions
USEFUL FOR

Physics students, educators, and researchers interested in the intersection of classical mechanics and electromagnetism, particularly those exploring the behavior of electric charges in motion.

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Hi,

Is Newton's 3rd law applicable to electric charges?

I have a problem with a situation where two identical positive charges moving perpendicular to each other. The magnetic forces exerted by each one on the other have same magnitude but their directions are not opposite.
 
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NIII does not hold for moving charges. The momentum of the electromagnetic fields changes for two moving charges, so the sum of their mechanical momentum is not conserved.
 
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there is a Newton's third?
 

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