Magnets Should Run Out of Energy, So Why Don’t They?

Magnets Should Run Out of Energy, So Why Don’t They? A magnet should run out of power, so why doesn't it? The little magnet on your fridge might have held up the same drawing for twenty years. It has no battery and no fuel, and nobody has ever charged it. Your phone dies, your car runs out of gas, and even the Sun is slowly burning through its fuel. So where does a magnet's energy come from, and why doesn't it ever run down? In this calm, step-by-step physics explainer, told in simple words anyone can follow, we start with a surprising truth: holding something still takes no energy at all. We look at why your arm gets tired but a table doesn't, why a scrapyard electromagnet burns electricity, where the energy comes from when a paperclip snaps onto a magnet, and why every magnetic perpetual motion machine has failed, going all the way back to Peter Peregrinus in 1269. Then we go deeper. From lodestones and the first compasses to Ørsted, Ampère, and the Bohr–van Leeuwen theorem, we see why classical physics says magnets shouldn't exist at all. The answer comes from quantum mechanics. The Stern–Gerlach experiment and the discovery of electron spin showed that every electron is a tiny magnet that never wears out. We also cover the Einstein–de Haas experiment, the Pauli exclusion principle, Heisenberg's exchange interaction, and why iron, cobalt, and nickel are magnetic while most materials aren't. Along the way we meet magnetic domains, the crackling Barkhausen effect, neodymium magnets, the Curie temperature, the famous floating frog, magnetic rocks that have held their magnetism for hundreds of millions of years, the geodynamo that powers Earth's magnetic field, and superconducting MRI magnets whose currents flow for years without fading. If you've ever wondered how a magnet keeps pulling without ever getting tired, this video is for you. Subscribe for more calm, clear explanations of the deepest ideas in physics. #Physics #Magnets #QuantumPhysics #Magnetism #ElectronSpin #ScienceExplained