How EM waves are produced say by a capacitor of an LC circuit here if $E$ is increasing in upward direction?

My thoughts

Thought 1:-

If E is increasing E flux is increasing thus B field must be created by seen in counter clockwise direction from above. Earlier B field was zero now it is not thus B field has increase B flux is increasing thus an E filed is induced in all directions around the ring of B field and so on The problem is that the direction of propagation of wave here is opposite to the direction of E×B vector.

Thought 2'-

At an instant There is an electric field now if it is induced electric field then there must be a change in magnetic flux around thus there is a magnetic field. The magnetic field is in clockwise direction as seen from above.now if there is a magnetic field thus there is change in electric flux around the electric flux must be in upward direction around the magnetic field ring.The problem is here that the induction works the other way a changing electric flux through a region produces magnetic field as in the first thought but here we are saying that if there is electric field then there must be changing magnetic flux which would have produced it is it true. And if true wouldn't a constant electric field then would produce an EM wave. We can just assume that the initial electric field in capacitor is constant but still then according to thought 2 EM wave must be created.

If both these are wrong then please tell me how an EM wave is created

My thoughts on wave propagation

  • $\begingroup$ In both your sketches the arrows have to point in interchanging directions: E up, B left, E down, B right, ... $\endgroup$ – HolgerFiedler Dec 1 '19 at 18:04
  • $\begingroup$ I've only took account That the electric field in the capacitor is increasing for now.the wave is not sinusoidal. $\endgroup$ – gaurang agarwal Dec 2 '19 at 1:20

please tell me how an EM wave is created

First about EM radiation. Charges under acceleration emit EM radiation. The emission happens perpendicular to the direction of acceleration. For example, the synchrotron radiation is around the tangent of the accelerator ring. Accelerating a charge upwards the photons get emitted horizontally (in 360° around the wire).

To get an EM wave you simply has to drive your wire with an alternating current. The current modulate the EM radiation to a sinusoidal wave. Much better of course is to use a open circuit.

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  • $\begingroup$ I just want to go deeper in the same explanation . See here this is a changing electric field say It changes from E=0 to E=E0 in time t now what happens due to changing magnetic field. Electric flux is changing thus there must be a magnetic field surrounding which wasn't there before thus magnetic flux has just changed which will produce a corresponding electric field in nearby region. BUT the problem in this is that the direction of the corresponding magnetic field vectors I'm getting is just opposite to the actual direction of magnetic field so that the wave could propagate outward (E×B) $\endgroup$ – gaurang agarwal Dec 7 '19 at 8:12

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