Electric Fields in Conductors - in 5 minutes

Electric fields can interact with conductive materials, giving rise to phenomena of great significance. A conductor is defined as any material capable of allowing electric current to flow within it and along its surface. Conductors are divided into first-class conductors, when they have electrons free to move in the valence band of the atoms that compose the conductor, and second-class conductors, when they are ionic species capable of carrying current. Many metals and their alloys are first-class conductors, while saline solutions are second-class conductors. Electric fields, by their nature, exert Coulomb forces on electric charges, accelerating them. Therefore, if we place a metal object in an electric field, the field will apply a force to each of the trillions of free-floating electrons present in the metal. Each of these charges will move until a state of electrostatic equilibrium is reached, in which all the free charges are arranged on the surface of the conductor, while the electric field inside the conductor will always be zero. This equilibrium situation, however, is valid only under electrostatic conditions. As we have said, in conditions of electrostatic equilibrium, all the free charges are arranged on the surface of the conductor, which therefore becomes an equipotential surface. This means that the potential on this surface is constant, meaning it remains the same at every point of the surface. Since there are no potential differences, the charges arranged along this surface are practically stationary, and the system remains in equilibrium. Since the charged surface will still emit an outward electric field, defined by Coulomb's theorem: E = (σ/ε0)n Where E is the electric field, σ is the surface charge density, ε0 ​​is the dielectric constant of a vacuum (assuming the conductor is in a vacuum), and n is the unit normal to the surface. This field always has an outward direction and is perpendicular to the equipotential surface. If the conductor has one or more cavities inside it, nothing changes: even inside the cavities, the electric field will be zero, and the external surface of the cavity will have an equipotential surface. A particularly important phenomenon is electrostatic induction, not to be confused with electromagnetic induction. This phenomenon allows a charged conductor to transfer part of its charges to another conductor placed nearby. The most classic case is that of a negatively charged conductor with a cavity inside it, containing a second positively charged conductor. If the two conductors are not in contact, the inner surface of the hollow conductor becomes negatively charged because the positive conductor will attract the positive charges toward it. Consequently, the positive charges will accumulate on the outer surface of the hollow conductor. Once electrostatic equilibrium is achieved, the outer surface of the hollow conductor will have a charge equal in sign and quantity to that of the internal conductor. When two conductors form complete induction, they form what is called a capacitor, a device capable of storing electrical charge. Thanks to Dr. Luigi Rescigno for his scientific support. Table of Contents 0:00:00 - Introduction 0:01:00 - 0:03:00 - Conclusions ____________ For quote requests, please write to: [email protected] ___________ ☆ A2C Website: https://a2c.it ☆ Facebook:   / aduec   ☆ YouTube: https://www.youtube.com/c/A2cIt?sub_c... ☆ LinkedIn:   / a2c---consulenza-tecnica   ☆ Telegram: https://t.me/a2c_it ____________ Podcast: 🎧 Anchor: https://anchor.fm/aduec 🎧 Google Podcasts: https://podcasts.google.com/feed/aHR0... 🎧 Apple podcasts: https://podcasts.apple.com/podcast/id... 🎧 Spotify: https://open.spotify.com/show/0uxSEWY...