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I'm absolute beginner at physics and try to build intuition by reading the Feynman lectures on physics.

First, I assume - if I understand well - that electromagnetic wave could be produced by a single oscillating charge (doesn't require dipole).

Second, positive and negative electric fields are corresponding to the potential force to be applied to a distant charge (attraction/repulsion).

enter image description here

My question is, if an oscillating charge generated an electromagnetic wave, does a distant charge "feels" attraction due to the positive part of the wave and repulsion due to the negative part of the wave?

enter image description here

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  • $\begingroup$ It's the acceleration of the charge that generates the EM wave. Oscillation inherently involves changes in direction and therefore involve acceleration. So oscillation is not necessary. Acceleration is. With that in mind you can see the mental model in the second image doesn't make any sense. Furthermore, another reason the second diagram doesn't work is nothing is physically distinct between up/positive or down/negative to ascribe attraction and repulsion. They're just opposite, but arbitrary directions. Rotate everything around the axis of travel by 45 or 90 degrees What then? $\endgroup$
    – DKNguyen
    Sep 14, 2022 at 20:59
  • $\begingroup$ Please clarify your specific problem or provide additional details to highlight exactly what you need. As it's currently written, it's hard to tell exactly what you're asking. $\endgroup$
    – Community Bot
    Sep 14, 2022 at 21:33

1 Answer 1

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Light does not carry a charge. It is attraction and repulsion of charges that creates the dynamics between charged bodies.

Suppose one has a pulse of light with its zillion oscilating fields, no attraction and repulsion exists between a charge further away because no field lines can be assigned/drawn from the charge to the light pulse.

If the pulse scatters off the charge, then there is interaction between the charge and the pulse, which is studied in various models, for example this one.

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  • $\begingroup$ Then what do the positive and negative parts of the wave represent? If a static electric field exists, it will generate an attraction/repulsion on another charge. In the wave, does the positive part represents a positive electric field? if yes, then why no attraction/repultion exists. If no, then what does it represent? $\endgroup$ Sep 15, 2022 at 11:06
  • $\begingroup$ The mathematical representation of aneelectromagnetic wave, obeying maxwell's equations. It is not the fields that attract or repulse, it is the charges. $\endgroup$
    – anna v
    Sep 15, 2022 at 11:48

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