What charges generate EM waves in free space?

[Kaushik Classes]

as we know light travel in vacuum because of oscillation of electric and magnetic field and both are perpendicular to each other. But i don understand how these electric and magnetic fields get generated in vacuum. as electric filed can vary by oscillating charge and that generate varying electric filed causing varying magnetic field. So what are these charge that travel with light to keep generating electric and magnetic field.

 

[stefan r]

There is no charge traveling with the photon.

When a photon is adsorbed it can move an electron. The electron has a charge.

 

[Kaushik Classes]

There is no charge traveling with the photon.

When a photon is adsorbed it can move an electron. The electron has a charge.

but how these electric field get generated?could you please explain this concept?

 

[Nugatory]

but how these electric field get generated?could you please explain this concept?

A changing magnetic field will create an electric field and vice versa; this is described by Maxwell's equations. Thus, if you can accelerate a charge in a way that starts the electrical and magnetic fields changing, the change will continue to propagate.

If you google for "Maxwell's equation wave" you'll find the detailed derivation.

 

[Dale]

But i don understand how these electric and magnetic fields get generated in vacuum.

I wouldn’t say that they get generated in vacuum. They get generated by charges, and then they propagate through vacuum. This is described by Jefimenko’s equations

https://en.m.wikipedia.org/wiki/Jefimenko's_equations

 

[Kaushik Classes]

I wouldn’t say that they get generated in vacuum. They get generated by charges, and then they propagate through vacuum. This is described by Jefimenko’s equations

https://en.m.wikipedia.org/wiki/Jefimenko's_equations

Agree with you . as once they are generated electric and magnetic field sustain each other and they progress.
so how does the sun light travel and what is the mechanism that generate the electromagnetic wave from sun?

 

[Dale]

so how does the sun light travel

https://en.m.wikipedia.org/wiki/Maxwell's_equations

and what is the mechanism that generate the electromagnetic wave from sun?

Primarily black body radiation.

 

[tech99]

Agree with you . as once they are generated electric and magnetic field sustain each other and they progress.

But first of all, an electric field can exist in a vacuum somehow. And so can magnetism.