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We know that a moving charge produces a magnetic field. But which frame of reference it must move to produce magnetic field? And also if a charged particle moves in a magnetic field, magnetic force acts on it. In which frame of reference it must move to feel a force?

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We know that a moving charge produces a magnetic field.

We know that a field that is purely electric in one frame of reference will, in general, be a mix of electric and magnetic fields in relatively moving reference frames.

In a frame of reference in which an isolated point charge is not moving, the field of the point charge is purely electric.

But, as observed from a relatively moving reference frame, the field will in general, have a magnetic component.

In which frame of reference it must move to feel a force?

Honestly, I don't quite understand the motivation for your question. A charged particle that "feels" a force in one frame must according to any frame.

Now, in the particle's frame of reference, the particle is by definition at rest and thus the force is purely electric in nature. From a relatively moving frame, the force has a magnetic component. Recall from above that the electric and magnetic fields "mix" as we transform from a reference frame to a relatively moving reference frame.


Based on a comment below from the OP, I think I now see what the question actually is so the following is an attempt to answer that.

If a charged particle is at rest in a purely magnetic field, there is no electric or magnetic force on the particle. The particle is not accelerated; there is no net force on the particle.

But, from some relatively moving frame of reference, the charged particle is moving in a magnetic field so there must be a magnetic force acting on the particle.

However, in this moving frame, what was a purely magnetic field is now some mix of electric and magnetic fields.

And, since there is no net force on the particle, it must be the case that the electric force acting on the particle is equal and opposite to the magnetic force.

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Thankyou sir for your support but when a particle is said to be in rest in a magnetic field it feels no force either electric or magnetic. But when moving it feels force either electric or magnetic or both. In which frame of refrence it must be in rest to feel no force either electric or the other. And in which it must move to feel any of these force. –  Rahul Goswami Nov 21 '13 at 15:38
    
@RahulGoswami, as I write above and once again, if a particle feels force in any reference frame, it feels a force in all reference frames. An accelerometer attached to the particle either reads zero or it doesn't, period. This reading is not frame dependent. It is the nature (pure electric, pure magnetic, or mixture) of the force that is frame dependent. –  Alfred Centauri Nov 21 '13 at 16:00
    
Okay if force is felt by it then accelerometer will read in all frame.. but charge in rest in a magnetic field feels no electric or magnetic force so in what refrence it must be in rest so that no electric or magnetic force acts on it. –  Rahul Goswami Nov 21 '13 at 17:18
    
@RahulGoswami, your question in the comment above simply doesn't make sense to me as written. I've made an honest effort to understand what you're attempting to ask here and I believe the answers I've given to be correct. Since you continue to ask what appears to me to be a very confused question, I don't see that there is any profit in continuing this. –  Alfred Centauri Nov 21 '13 at 19:17
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