ALL OF PHYSICS explained in 14 Minutes

Floating in the vast expanse of space, fundamental laws govern the motion of rocks, gas, and celestial bodies. Newton’s equation, F = ma, shows that any push or pull on a fixed mass produces a predictable acceleration, a principle that applies from falling apples to orbiting planets. The law of universal gravitation reveals that every mass attracts every other mass with a force that decreases with the square of the distance, orchestrating the elliptical paths of planetary bodies. This understanding distinguishes constant mass from variable weight, determined by the intensity of gravitational fields.

Energy exists in two primary forms: kinetic, the energy of motion, and potential, the stored energy due to an object's position, such as a phone held above the ground. Work is the process of applying a force over a distance, converting stored energy, like lifting an apple which shifts chemical energy into gravitational potential energy. Energy is conserved, meaning it only changes form, as shown when a moving car's kinetic energy becomes heat through friction and disperses into the surrounding air. Temperature directly reflects the average kinetic energy of atoms, where increased movement results in a hotter state.

Thermodynamics shows that natural systems evolve from organized, low-entropy states to disordered, high-entropy ones, as seen when an ice cube under the sun transforms into water with countless configurations. The measure of entropy quantifies this disorder and explains why energy becomes less useful for doing work after conversion. The universe’s overall trend towards higher entropy also underlies the unidirectional flow of time, and even localized reductions in entropy, like water freezing, ultimately contribute to an increase in total disorder.

Electromagnetism is powered by the flow of electrons, where voltage propels negatively charged particles through a resistive medium to create currents and light. Coulomb’s law explains that opposite charges attract while like charges repel, a principle akin to gravitational interactions. Maxwell’s equations reveal that stationary charges create electric fields, and moving charges or magnets induce magnetic fields that continually influence each other through induction. This intricate interplay of static and dynamic fields generates electromagnetic waves, spanning visible light to the invisible spectrum used in modern communication.

Molecules are built from atoms that consist of a nucleus with protons and neutrons, accompanied by orbiting electrons. Protons and neutrons themselves are composed of quarks, forming the core of the standard model that explains the universe's smallest components. Variations in proton and neutron counts lead to different elements and isotopes, with unstable isotopes decaying and releasing ionizing radiation as defined by their half-life.

Light travels at an astounding 299,792,458 meters per second in a vacuum, displaying its wave nature through interference and its particle nature via discrete photons. The constant speed of light demands that time adapts relative to different frames, unifying perception regardless of motion. Gravity, reimagined as the bending of spacetime by mass, shows that objects follow natural, straight paths in a curved fabric. This insight reshapes our understanding of the universe by linking the behavior of light with the fundamental geometry of space and time.

Energy and mass are equivalent, meaning even a tiny fraction of mass can release an enormous amount of energy. Fission splits an atomic nucleus into smaller fragments through neutron bombardment, converting a small mass loss into huge energy output. Fusion combines two lighter nuclei into a heavier one, with the released energy stemming from the mass defect between the initial and resulting nuclei. The processes underline the potential and peril of atomic reactions in unleashing concentrated energy.

Einstein’s insight that light behaves as particles combined with Planck’s discovery that energy comes in discrete packets laid the groundwork for quantum mechanics. Electrons exist in a superposition of states, with their probable positions described by a cloud-like distribution until measurement collapses them into one location. The Heisenberg uncertainty principle rules out knowing both the exact position and momentum of a particle simultaneously. The double slit experiment demonstrates that individual photons generate interference by traversing both paths as waves until observation forces them to choose a definite trajectory.