Can a time variable B field create

In summary, the Maxwell equations govern the electromagnetic field, with two dynamical laws and two constraint equations. A time-varying field does not directly cause an electromagnetic vortex field, but rather the true sources are the charge and current distribution. The Jefimenko equations provide a more accurate understanding of the relationship between time-varying fields and electromagnetic fields.
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physics user1
A static E Field and vice Versa?
Or a time variable field created also another time variable Field?
 
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Cozma Alex said:
A static E Field and vice Versa?
Yes, provided the rate of change of one field is constant w.r.t. time.
 
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The electromagnetic field is governed by the Maxwell equations. Written in terms of the usual three-vectors ##\vec{E}## and ##\vec{B}## (the electric and magnetic field components) there are four equations. Two of them are dynamical laws, describing the electromagnetic field as being caused by the charge and current distribution (i.e., on a fundamental level, by moving charged particles). The other two are constraint equations: One is Faraday's Law, and the other is Gauss's Law for the magnetic field:
$$\vec{\nabla} \times \vec{E}+\frac{1}{c} \partial_t \vec{B}=0, \quad \vec{\nabla} \cdot \vec{B}=0.$$
The first one is sometimes misunderstood in the way that a time-varying (it doesn't matter whether the change is linear with time or not, by the way) causes an electromagnetic vortex field. Also Faraday's Law looks like this, it's physically a bit misleading to think in such a way. It turns out, that when you mathematically follow this idea that the equations for the solutions of the Maxwell equations become pretty complicated and non-local.

On the other hand, there are the Jefimenko equations, which are nothing else than the retarded solution of the Maxwell equations, which clearly show that the true sources in the sense of a local field theory are the charge and current distribution. For more details, see also

https://www.physicsforums.com/threads/induced-electric-fields.760783/#post-4792449
 
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Related to Can a time variable B field create

1. Can a time variable B field create electric fields?

Yes, a time variable B field can create electric fields through Faraday's law of induction. This law states that a changing magnetic field will induce an electric field, which can be measured in volts per meter.

2. How does a time variable B field affect charged particles?

A time variable B field can exert a force on charged particles, causing them to experience acceleration. This is due to the Lorentz force law, which describes the force on a charged particle in a magnetic field.

3. Can a time variable B field be used for time travel?

No, a time variable B field cannot be used for time travel. While it can affect the movement of particles, it cannot manipulate time itself. Time travel is currently only theoretical and has not been proven to be possible.

4. How is a time variable B field created?

A time variable B field can be created through various methods, such as using a coil of wire with an electric current flowing through it or using a changing magnetic field from a permanent magnet. It can also be created through natural phenomena, such as the Earth's magnetic field.

5. What are the applications of a time variable B field?

A time variable B field has many applications, including in generators, motors, and transformers. It is also used in medical imaging techniques like MRI machines and in particle accelerators. Additionally, it is being researched for potential use in quantum computing and communication.

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