There is a "dual" of electric dipoles: the magnetic loop (or magnetic dipole). The rule of wavelengths doesn't apply as it does for electric dipoles. The latt

There is a "dual" of electric dipoles: the magnetic loop (or magnetic dipole). The rule of wavelengths doesn't apply as it does for electric dipoles. The latter is true only because the tips of the dipole must be at zero (0V) at the tips to maintain proper boundary conditions to allow a voltage to apply at the dipole terminals. There is no such boundary condition for a magnetic loop. Low frequency (medium wave AM and below) thus can use magnetic loop antennas without this limitation. The wavelength of LF and VLF can be kilometers and that can never be a practical radio antenna. So it's not used - loops are used. Note that this electrical wavelength does match power transmission line dimensions which is why the long wavelengths of EMP primarily match and will disrupt power grids and NOT cell phones, etc. as wrongly portrayed in movies. EMP is a pulse but not an ideal Dirac impulse thus it has a finite bandwidth. It is equivalent to a signal with a 1st dominant pole at 1 MHz (the middle of the AM band) and then another pole at 100 MHz (the middle of the FM band) and by the time you hit cellular frequencies, the signal is 80 dB down from VLF levels. Add to this the reality that ESD is a thing so all ICs used in cellular radio are pretty pulse resistant. So the power grid is really the only "piece of metal" that can or will couple EMP. And power grids also deal with impulses and have protection against then: because lightning is a routine and common thing so there are circuit protections again that which also work just find against lightning which has a very simply frequency content.