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Electric currents and electromagnetic waves

Electric currents and electromagnetic waves

It is assumed by ,,classical electrodynamics” that an accelerated charge produce electromagnetic waves. An electric current is produced, according to the same classical electrodynamics, due to the accelerated charge (in case of metallic conduction this charges are electrons) moving through conductor under a potential difference.
Consequently around a conductor, there must be an emission of electromagnetic waves.
The present experiment has as purpose to detect these electromagnetic waves around a conductor in case of a continuous or alternating current.
For the experiment some radiofrequency meters for different bands (KHz, MHz, GHz, THz) are necessary. These are available now in specialists market or on the net, too.
A simple circuit composed by a source of current and a resistor is built. For the experiment a current greater then 1 A is used and the conductors are without mantle of isolation in order to facilitate the detection of electromagnetic waves around it. Moving the radiofrequency meters around circuit there is the possibility to measure the emission of electromagnetic wave.
First a direct source is used and the electromagnetic waves around conductors are measured.
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Figure 1. DC circuit and electromagnetic waves

Contrary to our expectations, a direct current does not emit electromagnetic waves in radio or microwave domain. In the same time the conductor get warm so emission of photons in IR and, depending on the temperature even in visible domain, is registered.
Using a source of alternate current, the same negative results are obtained for radio and microwave domain emission. Even the alternate current has a frequency of kHz, there is no emission of electromagnetic waves on the same frequency around conductor.
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Figure 2. AC circuit and electromagnetic waves

If a part of metallic conductor is replaced by ionic conductor again no emission of electromagnetic wave is observed around it.
The simple conclusion regards the impossibility of producing electromagnetic waves using simple electric currents. Around an electric current only a magnetic field, constant at a certain distance for a continuous current and variable in case of alternate current, is counted.
There is necessary a special device called ,,oscillating circuit'', which is able to produce electromagnetic waves. Actual ,,classical" electrodynamics and Maxwell equations are unable to make a difference between an alternate current and a electromagnetic wave produced by a oscillating circuit. In further study about electrodynamics there will be a clear separation between electric current and electromagnetic waves.

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