Looking Inside without Hurting. Magnetic Resonance Imaging

At first glance it looks like a giant
doughnut wrapped in hard plastic.
A second look reveals that it is a
magnetic resonator. That torus (the
doughnut) is actually a giant coil
made up of superconducting wires that transmit
large electrical charges. Faraday said it in 1831: these
electric charges produce a magnetic field. Certainly,
a warning indicates in large letters that we should
not approach with metals, as it is a giant magnet.
With such a powerful magnet it is possible to
induce the phenomenon of magnetic resonance in
the nucleus of atoms, the most abundant of which,
in biology, is hydrogen. Using electromagnetic
wave emissions (radio frequencies) perfectly tuned
to the resonant frequency, we can modulate the
magnetic properties of these atoms and thus
obtain information about the tissue. These are
the fundamental foundations that make magnetic
resonance imaging (MRI) possible, a technique