Physics
The study of matter, energy, space, and time.
Subcategories
- Electromagnetism — The unified physics of electric and magnetic fields.
- Quantum Mechanics — The physics of the very small: quanta, waves, and measurement.
Articles (11)
- Auroras: The Science of the Northern and Southern Lights
How auroras glow: solar particles racing down Earth's magnetic field lines excite oxygen and nitrogen high above the poles — the colour reveals which gas and altitude. - Fiber Optics and Total Internal Reflection
How light is trapped inside hair-thin glass strands by total internal reflection — the physics that carries the internet as pulses of light. - The Gyroscope
Why a spinning wheel resists being turned — angular momentum, precession, and the sensors that guide everything from bicycles to spacecraft. - How Microwave Ovens Heat Food
A microwave oven heats by rotating polar molecules in an alternating electric field — why water heats, why ice is slow, why plates stay cool, and what the metal warnings mean. - How Loudspeakers Work
From amplifier current to sound pressure: the moving-coil driver, why cabinets matter, crossovers, and the physics that limits every speaker no matter its price. - How Solar Cells Work
The photovoltaic effect: how a silicon junction turns photons into current, why panel efficiency sits near 20%, and what actually limits it. - Newton's Laws of Motion
The three laws of classical mechanics — inertia, F = ma, and action–reaction — that form the basis of classical physics. - Doppler Effect
The change in the observed frequency of a wave when the source and the observer move relative to each other. - Radioactive Decay
The spontaneous transformation of unstable atomic nuclei into other nuclei, emitting alpha, beta, or gamma radiation with characteristic half-lives. - Second Law of Thermodynamics
The law that entropy in an isolated system never decreases, fixing the direction of natural processes and limiting the efficiency of engines. - Special Relativity
Einstein's 1905 theory of space and time, built on the constancy of the speed of light and the equivalence of all inertial frames.