What Are EM Waves and How Do They Relate to Radiation?

[iScience]

i think I've asked this a number of times on different posts stemming from various discussions but i don't think this question was in the wrong thread. so I've decided to make a new thread for this.

so what 'IS' an EM wave? i understand that the acceleration of charges could produce a wave (disturbance) in the E-field, and hence a sinusoidal oscillation of the charge would produce an EM wave; if all EM radiation are the same, except for their wavelengths, then this implies that EM radiation is just a transverse wave in the electric field right? ie, it is a transverse wave of the electric field?

the process i gave describes the production of RF, which is radiated radially (in 2-D) from the antenna. but if you put a photodetector around the antenna, would it detect individual photons?

 

[Dale]

so what 'IS' an EM wave? i understand that the acceleration of charges could produce a wave (disturbance) in the E-field, and hence a sinusoidal oscillation of the charge would produce an EM wave; if all EM radiation are the same, except for their wavelengths, then this implies that EM radiation is just a transverse wave in the electric field right? ie, it is a transverse wave of the electric field?

It is a transverse wave in the electroMAGNETIC field. In an EM wave the magnetic field is perpendicular to the electric field and they are of equal magnitude (in units where c=1).

the process i gave describes the production of RF, which is radiated radially (in 2-D) from the antenna. but if you put a photodetector around the antenna, would it detect individual photons?

It would be very hard to detect individual photons in the RF range, their energy is extremely small. In principle, it could be done, but in practice I think it would be undetectable.

 

[Drakkith]

the process i gave describes the production of RF, which is radiated radially (in 2-D) from the antenna. but if you put a photodetector around the antenna, would it detect individual photons?

No, as a photodetector doesn't work in the microwave/radio frequency regions. The energy of each photon is simply too small to cause the photodetector to detect them.