Marcus Webb 
What is matter? Anything that has mass and occupies volume: protons, atoms, molecules, planets, and the coffee in your cup. That definition works until you push on the edges, where mass turns out to be mostly energy and volume turns out to be mostly nothing. Both surprises are worth understanding, because they change what the … Read more
What is energy? It is a number you can calculate for a system, which stays the same when nothing crosses the boundary, and which tells you what the system can do. That is a deliberately dry answer, because the honest definition is about bookkeeping rather than a glowing fluid. The word gets used as if … Read more
What is the speed of light? In vacuum it is exactly 299,792,458 meters per second, or about 186,282 miles per second. Since 1983 that number has not been a measurement. It is a definition, and the meter is the thing being defined by it. That reversal is the strangest part of the story. For three … Read more
What is relativity? It is two theories by Albert Einstein describing how measurements of time, space, and gravity depend on the observer. Special relativity, published in 1905, handles motion at constant speed. General relativity, finished in 1915, handles acceleration and gravity by treating gravity as the shape of spacetime rather than a force. Both are … Read more
Do we swallow spiders in our sleep? Almost certainly not, and the famous number — eight per year — was not discovered by anyone. It was written in 1993 by a magazine columnist trying to prove how easily a fake statistic could travel. The demonstration worked rather too well. The story is one of the … Read more
Is glass a liquid? No. Glass at room temperature is a solid — an amorphous one, meaning its atoms are frozen in a disordered jumble rather than a neat crystal, but frozen all the same. The famous evidence, those wavy medieval windows that are thicker at the bottom, is a story about how panes were … Read more
The coriolis effect toilet myth is a staple of airport conversation: water supposedly drains counterclockwise north of the equator and clockwise south of it. It does not. In any normal bathroom, the direction is decided by the shape of the bowl, the angle of the jets, and whatever currents were left in the water when … Read more
Do goldfish have a 3 second memory? No. Trained goldfish have retained what they learned for weeks and, in at least one controlled study, for months. The three-second figure has no research behind it at all — it is a number that spread because it is memorable, not because anyone measured it. The myth is … Read more
Does lightning strike twice? The proverb insists it never does. The records say it happens constantly, and to the same structures, in the same afternoon. The Empire State Building is struck roughly 23 to 25 times a year. A single thunderstorm can hit one radio tower a dozen times in an hour. The saying survives … Read more
How do computers store data? By holding a physical state that can be read back later. A flash cell traps electrons. A hard disk magnetizes a patch of cobalt alloy. A stick of memory holds a charge in a capacitor that leaks within milliseconds and must be refreshed thousands of times per second. Every file … Read more