British scientist Michael Faraday is the creator of the Faraday cage, a structure that serves as protection against static electric fields from outside.
The Faraday cage is a metal structure whose purpose is to provide protection against electrical discharges . It is a tool used in telecommunications , rooms where MRIs are carried out and laboratories , for example. It should be noted that the objective of this box is to prevent an electric field from the outside from influencing it, which is why it is shielded against electromagnetic waves that come from the environment.
Michael Faraday , a British scientist, was the one who invented this development that serves, to detail a specific case, to prevent radiofrequency from outside from interfering in the taking and generation of images of medical equipment that works inside the cage. .
This expert's discovery came from an electrostatic experiment that he carried out using an ice cube. He managed to demonstrate with his test what and how the effect that electrostatic induction has on a container that serves as an electrical conductor . According to their work, the electric charge accumulates only in the external area of a conductor that is charged and, thus, the electric fields end up canceled inside.
How a Faraday cage works
It is very interesting to know how a Faraday cage works, for that reason we are going to provide data about it.
When it comes to understanding the usefulness and characteristics of this particular box, it is necessary to master a series of concepts and know certain principles of Physics .
First of all, it is vital to know what Gauss's law is about, a postulate linked to Gauss's theorem (even called the divergence theorem). This statement formulated by the German physicist and mathematician Carl Friedrich Gauss says that the flow evidenced by some fields on a closed surface is proportional to the magnitude of the sources of the aforementioned field present within the same surface. It can be applied, with sources such as mass and electric charge , respectively, to the gravitational field and the electrostatic field . It should not be overlooked that Gauss's law oriented to both the magnetic field and the electric field nourishes, together with the Faraday-Lenz law and the Ampere-Maxwell law , a set of equations that have become popular under the name of equations of Maxwell . Another piece of information related to Gauss's law : it serves to reach the content of Coulomb's law , while at the same time it leads to Gauss's law .
The construction of Faraday cages is taken into account in numerous areas, being carried out for example for medical and telecommunications issues.
Magnetic shielding (alternative based on materials and techniques that reduce or guarantee the blocking of electromagnetic interference ) and protection against EMI (electromagnetic interference) are other issues of interest regarding the Faraday cage . Experts on the subject differentiate between intentional electromagnetic interference (with signals that are emitted on purpose, with a specific intention) and unintentional (undesired effects resulting from accidental propagation), as well as distinguishing between conducted electromagnetic interference (as happens with electrical networks, to describe a specific reality) and radiated electromagnetic interference (those that occur when the signal spreads through electromagnetic radiation ).
It is also important to be aware of the null condition of the electric field that is located inside the Faraday cage , an enclosure with a metal cover whose effect is replicated inside a car or aircraft and inside the cockpit. an elevator, beyond not being environments designed to block electric fields .
Applications and scope of Michael's invention
Let us now look at the applications and scope of Michael Faraday 's invention. Before detailing areas of use or exploitation of this cage, it is worth mentioning that there are numerous designs, materials, sizes and formats to take into account when wanting to create this type of structure.
In the case of devices used to carry out medical studies, each Faraday cage must be made respecting a construction protocol that establishes what elements to use, how to locate the enclosure and what dimensions it should have. Thus, this box prevents any external electric field from generating interference and causing alterations in the operation of the device.
A Faraday cage is essential to protect and keep technological equipment at the service of human health protected, such as machines for performing magnetic resonance imaging.
Knowing how the Faraday cage works and what effect it has, we can understand how it can influence mobile telephony (an area with equipment capable of emitting signals even when they are turned off), since it generates communication blocks for each device with the exterior plane.
A type of Faraday cage-style lightning rod has also been designed that benefits buildings because it keeps them protected in the event of lightning strikes.
With the opposite effect to what is noticed when studying the distinctive features of these boxes, the microwave oven appears, a device widely used in homes. In this case, the microwaves should not escape but remain inside the cubicle and cause the appliance to heat food products when it comes into operation.