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Aspchizo
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Can someone explain the difference? thanks.
He says the magnetic and electric field are working in opposition to each other. I don't understand this. If someone could give me a explanation for this that would be great.
vanhees71 said:There is no "difference". There is one and only one electromagnetic field. What you call electric and magnetic field depends on your reference frame, and it is rather a splitting in electric and magnetic components of this field (like you split your space-time vector wrt. to a reference frame in one temporal and three spatial components).
Maybe you shouldn't be so quick to attack vanhees like that don't you think? The electromagnetic field is described by the 2 - form [itex]F_{ab}[/itex] which goes by many names but I like electromagnetic field strength tensor. The components of [itex]F_{ab}[/itex] are split up into components of the magnetic and electric field but the 2 - form itself encapsulates the electromagnetic field. Other than the main diagonal, which is always zero, which components of [itex]F_{ab}[/itex] are zero or non zero depends on the frame of reference and as noted the components correspond to components of the E and B field. Maxwell's equations can be written down entirely in terms of [itex]F_{ab}[/itex] and the 4 - current density, as you can see in my signature. So really you just have the electromagnetic field as the one, all encompassing object and the components of the E and B field are frame dependent components of [itex]F_{ab}[/itex]. What vanhees said is probably one of the most beautiful things about electromagnetism.Menaus said:Ugh... NO!
Well the OP's question was rather ambiguous and vague to begin with so it is hard to gauge (no pun intended ) what to respond with. If the OP was more specific then more detailed responses could be constructed but as it is stands, the OP should have researched his very broad question first, otherwise it is only natural to get a large spectrum of responses. I don't see how it is showing off and honestly I think it motivates people to go learn about the deep connections between the E field, B field, and special relativity because this is one of the most amazing things about electromagnetism imo.ModusPwnd said:I think its just needless showing off... If somebody asked what was the difference between energy and momentum you wouldn't reply "no difference" and appeal to relativity. No, you would explain the difference and then add in some about their connection.
Yes, there is the force due to the electric field and the force due to the magnetic field. In region 1, he wants these two forces to be equal and opposite so that the total force on the charge is zero. Therefore, he does some calculations to find out what the electric field and magnetic field values must be, so that the total force on the charge would be zero. Note that in general, the two forces are not usually equal and opposite, it is just in the particular example he gives, he wants them to be equal and opposite, so that the charge will go through the little 'gap' he drew.Aspchizo said:He says the magnetic and electric field are working in opposition to each other. I don't understand this. If someone could give me a explanation for this that would be great.
ModusPwnd said:Cant transform an electric field completely away though. I think his remark was snarky and missed the point of the question. There is a difference. Yes, you can transform some of one into the other. Regardless, there is a difference. I think its just needless showing off... If somebody asked what was the difference between energy and momentum you wouldn't reply "no difference" and appeal to relativity. No, you would explain the difference and then add in some about their connection.
WannabeNewton said:Well the OP's question was rather ambiguous and vague to begin with so it is hard to gauge (no pun intended ) what to respond with. If the OP was more specific then more detailed responses could be constructed but as it is stands, the OP should have researched his very broad question first, otherwise it is only natural to get a large spectrum of responses. I don't see how it is showing off and honestly I think it motivates people to go learn about the deep connections between the E field, B field, and special relativity because this is one of the most amazing things about electromagnetism imo.
Aspchizo said:Is this because the question is so short and vague?
In some cases you can. If you have an E and a B field in a given frame and if B²-E²/c² is greater than 0 then there is a reference frame where E=0.ModusPwnd said:Cant transform an electric field completely away though.
A magnetic field is created by moving electric charges, while an electric field is created by stationary electric charges. Additionally, magnetic fields are generated by magnets, while electric fields are generated by electrically charged particles.
Magnetic fields and electric fields can interact with each other in a phenomenon known as electromagnetic induction. This occurs when a changing magnetic field induces an electric field, and vice versa.
Magnetic fields have various applications, such as in motors, generators, and medical imaging devices. Electric fields are used in electronic devices, such as capacitors and transistors, and in power transmission systems.
Both magnetic fields and electric fields can have potential health effects at high levels. Exposure to strong magnetic fields can interfere with pacemakers and other medical devices, while high levels of electric fields can cause burns or shocks.
Magnetic fields and electric fields can be measured using specialized instruments such as magnetometers and voltmeters. These instruments can detect the strength and direction of the fields, allowing scientists to analyze and understand their behavior.