Electromagnetism question, what formula

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To analyze the interaction between electric and magnetic fields while moving through a uniform magnetic field, the Lorentz transformation equations are essential. When moving perpendicularly to a magnetic field, an electric field is generated, while moving parallel does not create an electric field. The velocity of the observer significantly impacts the observed fields, especially if the velocity changes over time. The transformation equations provided by J.D. Jackson illustrate how electric and magnetic fields change between different inertial frames. Understanding these concepts is crucial for anyone studying electromagnetism, particularly in advanced courses.
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I'd like to know what formula to use in order to find the following :
Imagine a uniform magnetic field. I am moving with a constant velocity perpendicularly through it. Do I see only an electric field? A magnetic field? Both? Or both of them?
What if I move in the sense of the magnetic field with a constant velocity?

What if my velocity changes with time?
What if, instead of the magnetic field, it's an electric field?

I do not expect the answer to all these questions, rather I'd like a formula to check it out myself. But if you have to say a word or even give the answer, I'm all ears.
Thanks in advance.
 
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What velocity are you traveling with? If it's much lower than the speed of light:

9cab6787646062d6e658cd1e83ad468f.png
 
Pythagorean said:
What velocity are you traveling with? If it's much lower than the speed of light:

9cab6787646062d6e658cd1e83ad468f.png
Thanks a lot. I'm a bit confused, if B is uniform, if I move, \frac{\partial B}{\partial t}=0 or I'm wrong?
 
To look at EM in another velocity you need to use a lorentz transformation of the field. If you are familiar with vectors, J.D. Jackson p. 558 gives a useful form:

\vec{E}' = \gamma (\vec{E} + \vec{\beta} \times \vec{B}) - \frac{\gamma^2}{\gamma + 1} \vec{\beta} (\vec{\beta} \cdot \vec{E})

\vec{B}' = \gamma (\vec{B} - \vec{\beta} \times \vec{E}) - \frac{\gamma^2}{\gamma + 1} \vec{\beta} (\vec{\beta} \cdot \vec{B})

\vec{\beta} = \vec{v}/c
\gamma = \frac{1}{\sqrt{1 - \beta^2}}

So, you see if you have one frame where E = 0, and only B != 0. Then in every other frame E' != 0, and B' != 0, since B appears in both terms.
 
kcdodd said:
To look at EM in another velocity you need to use a lorentz transformation of the field. If you are familiar with vectors, J.D. Jackson p. 558 gives a useful form:

\vec{E}' = \gamma (\vec{E} + \vec{\beta} \times \vec{B}) - \frac{\gamma^2}{\gamma + 1} \vec{\beta} (\vec{\beta} \cdot \vec{E})

\vec{B}' = \gamma (\vec{B} - \vec{\beta} \times \vec{E}) - \frac{\gamma^2}{\gamma + 1} \vec{\beta} (\vec{\beta} \cdot \vec{B})

\vec{\beta} = \vec{v}/c
\gamma = \frac{1}{\sqrt{1 - \beta^2}}

So, you see if you have one frame where E = 0, and only B != 0. Then in every other frame E' != 0, and B' != 0, since B appears in both terms.

Ok thank you very much. I'm going to try to grasp this. I took vector calculus. I'm taking the 1 year EM course on next term (in March). I thought I would need it for the intro to EM course, but I'm not sure now. Anyway, I'll do an effort to learn this part.
 
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