Magnetic Force and Frame of Reference

In summary, the conversation discusses the concept of a charged particle moving perpendicular to a magnetic field and the resulting force on the particle. The answer provided by the speaker suggests that when in an accelerated reference frame, the observer will not observe any force on the particle due to pseudo forces. However, the other person in the conversation argues that the solution to this conundrum is not related to accelerated frames, but rather the transformation of electromagnetic fields under changes in inertial frames. This means that the force observed in the original frame may appear differently in the particle's instantaneous rest frame. The conversation also touches on the idea that magnetic force is not a real force, but rather a combination of electric and magnetic forces.
  • #1
UncertaintyAjay
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So, a friend asked me this question in school and I've come up with an answer, I'm just not sure that it is right.
Say you have a charged particle moving perpendicular to a magnetic field. There will be a force acting on it given by F=qvB.
Now suppose your'e moving along at the same velocity as said particle. It's velocity respective to you is zero, so you should not observe any magnetic force even though there is one.

My answer is this:
From an inertial frame, the charged particle will be moving in a non-inertial reference frame. So if you move along at the same velocity as the particle, yours is an accelerated reference frame too and you don't observe any force on the particle because of pseudo forces.
Is this right?
 
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  • #2
No. You can always place yourself in an inertial frame where the particle is momentarily at rest. The solution to your conundrum has nothing to do with accelerated frames. It is based on the fact that the electromagnetic fields transform under changes of inertial frames. What might have been a pure magnetic field in your original frame will be a combination of electric and magnetic fields in the instantaneous rest frame of the particle. What appeared as a magnetic force in your original frame is an electric force in the particle rest frame.
 
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Likes UncertaintyAjay
  • #3
Thanks a lot!
 
  • #4
No. Magnetic force is not a real force, Neither is electric force. Only sum of magnetic and electric force (electromagnetic force) is a real force. What your friend said was absolutely correct. Force is frame independent and velocity is frame dependent. Then how the hell can we relate these two? It completely violates the rules of inertial frame and non inertial frames.
Also seeing your friends statement, we can conclude that magnetic force is not really a force. And by the way your statement is wrong. The charged particle will move in an inertial frame, as it is moving with a constant velocity.
 
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FAQ: Magnetic Force and Frame of Reference

1. What is magnetic force?

Magnetic force is a force that is exerted by magnets and magnetic fields on magnetic objects. It is a fundamental force of nature, along with gravity, electricity, and the strong and weak nuclear forces.

2. How does magnetic force work?

Magnetic force works by the interaction between magnetic objects or materials. It is caused by the movement of charged particles, such as electrons, within a magnetic field.

3. How is magnetic force measured?

Magnetic force is measured using a unit called the Tesla (T). This unit measures the strength of the magnetic field and is equivalent to one Newton of force per ampere of current per meter of wire.

4. What is the relationship between magnetic force and frame of reference?

The magnetic force on an object can vary depending on the frame of reference. In the frame of reference of the magnetic field, the force is the strongest. However, in a different frame of reference, the force may appear weaker due to the object's motion or orientation.

5. How is magnetic force used in everyday life?

Magnetic force has many practical applications in everyday life. It is used in technologies such as electric motors, generators, and MRI machines. It is also used in household items like speakers, computer hard drives, and credit cards.

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