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As we all know that Electromagnetic waves are produced by a oscillating charge , whose electric field is shown below in diagram.

electromagnetic waves

**Now here what is Electromagnetic wave - Complete pattern Or just a component of that pattern if that please draw a simple diagram for oscillating charge electric field to show what is actually radiation.

And why this pattern is not same as diagram used in our textbooks ? -

enter image description here

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  • $\begingroup$ Related post by OP: physics.stackexchange.com/q/773433/2451 $\endgroup$
    – Qmechanic ♦
    Commented Jul 25, 2023 at 11:57
  • $\begingroup$ It would seem the animated diagram shows the near field, while the other the far field (it misleadingly placed a red dot labeled 'q' where it should not be for a far field.) $\endgroup$
    – Jens
    Commented Jul 26, 2023 at 14:06
  • $\begingroup$ @Jens do you have any animation or simulation which shows electric field of charge for far field. $\endgroup$
    – Govind Prajapat
    Commented Jul 27, 2023 at 15:57
  • $\begingroup$ @GovindPrajapat Maybe something here: duckduckgo.com/… $\endgroup$
    – Jens
    Commented Jul 28, 2023 at 7:56

2 Answers 2

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The textbook figure you have here is for a transverse electromagnetic mode (TEM), which only has variations in two directions ($\hat y$ and $\hat z$), and moves in a third ($\hat x)$. These TEM-modes have particularly simple solutions. In more realistic cases, such as with moving charges and antenna's, the fields generated are far more complicated. The textbook figure is then educational, illustrating the main features of a simple case, while realistic cases have solutions more like the animation you added.

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I don't know if I am correct or not , but I will try to answer.

If we analyse a simple case , a particle , which is at rest at t=0 , accelerates for small time ∆t , and them moves with constant velocity, we observe a kink in electric field at time t>>∆t.

enter image description here enter image description here

Further if we derive the expression for Transverse electric field in kink , we find it proportional to 1/r.

As far as I know, the electromagnetic wave of oscillating charge is inversely proportional to r.

So now I think that transverse electric field is EMW not complete electric field. ( radial + transverse ) Correct Me If I Am Wrong.

Reference - Electromagnetic Vibrations, Waves and Radiation by Bekefi and Barrett

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