Q vxB Magnetic Force: Reconciling Two Situations

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SUMMARY

The discussion centers on the apparent contradiction in the behavior of a charged particle in a magnetic field when analyzed from different reference frames. In the first scenario, a charge q moving with velocity v in a magnetic field B experiences a force F=qvB along the z-axis. However, in a second reference frame moving at the same velocity v, the force F becomes zero, indicating no magnetic force acts on the particle. This discrepancy highlights the necessity of incorporating special relativity to reconcile the differing observations of magnetic force across reference frames.

PREREQUISITES
  • Understanding of classical electromagnetism, specifically Lorentz force law.
  • Familiarity with reference frames and relative motion.
  • Basic knowledge of special relativity principles.
  • Concept of magnetic fields and their interaction with moving charges.
NEXT STEPS
  • Study the Lorentz force law in detail, focusing on its implications in different reference frames.
  • Explore the principles of special relativity, particularly time dilation and length contraction.
  • Investigate the relationship between electric and magnetic fields in moving reference frames.
  • Review resources on electromagnetic theory, such as the provided links on magnetic forces in different frames.
USEFUL FOR

Physics students, educators, and anyone interested in advanced electromagnetism and the implications of special relativity on magnetic forces.

eltodesukane
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there is something I don't understand
maybe someone can tell me

- a charge q has velocity v along the x axis
- there is a uniform magnetic field B along the y axis
- so the particule experience a force F=qvB along the z axis

Now consider the same situation in a reference frame moving at velocity v along the x axis.
Now F=qvB=0 and there is no force on the particule.

What am I missing?
How to reconcile those situation?
 
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