Matter, Energy & Physics
Everything, from a grain of sand to a galaxy, is made of the same few particles obeying the same few laws. These readings explain what matter is, what energy is, and the strange rules that govern the very small.
8 articles · about 31 minutes of reading
Matter, Energy & Physics
Atoms
Everything you can touch is made of atoms, and atoms are almost entirely empty space. Here is what they are, how we know, and why the tiny nucleus holds so much power.
Article · 4 min read
Matter, Energy & Physics
Electricity and Magnetism
Lightning, compasses, motors, radio and light itself are all one phenomenon. Discovering that they were the same was one of the great unifications in science.
Article · 4 min read
Matter, Energy & Physics
Energy and Heat
Energy cannot be made or destroyed, only moved and changed. Heat is the form it always ends up in, and that one-way street explains why time has a direction.
Article · 4 min read
Matter, Energy & Physics
Gravity
The weakest force in nature holds planets in orbit, lights the stars and shapes the universe. Newton described it; Einstein explained it as the bending of space and time.
Article · 4 min read
Matter, Energy & Physics
Light
Light is a wave, a particle and the fastest thing there is. Everything you see is light that has bounced, bent or been born, and the colours of the rainbow are only a sliver of it.
Article · 4 min read
Matter, Energy & Physics
Sound
Every sound you hear, from a whisper to thunder, is a vibration travelling as a pressure wave. Learn how sound moves, why pitch and loudness differ, and how animals use it.
Article · 3 min read
Matter, Energy & Physics
The Periodic Table
One chart holds every kind of atom in the universe, arranged so that its pattern predicts how each one behaves. Here is how to read it and why it works.
Article · 4 min read
Matter, Energy & Physics
The Quantum World
At the scale of atoms the universe stops behaving sensibly. Particles are waves, things exist in several states at once, and measurement changes reality. It is all true, and it runs your phone.
Article · 4 min read