When waves leave the wire?

[Amr Morsi]

At the electric wire radio wave emitting condition is different from visible wave emitting condition.

We can make visible light by using tungsten filament.

The temperature condition is very high. Visible light generating procedure is like this.

The electron current through the filament makes a high temperature, and at the hight temperature light is naturally emitted by electron orbital movement in the atom.

Then, How the radio wave is emitted on the surface of the copper wire?

 

Waves and spreads of electromagnetic field begins from every point of the wire inside the shielding. Some reflects back and other penetrate it to the air. All being governed and described by Maxwell's Equations and by other field theories fro more exactness.