Combustion is a push. Everything in an engine exists to convert a series of pushes into smooth rotation, at speed, repeatedly, while managing the heat and friction that produces. Here…
There is a widespread assumption about roads that is understandable and backwards.
The assumption is that the hard black surface is the road, and that what lies beneath it is…
A moving bicycle with nobody on it can stay upright for a considerable distance, correcting itself when pushed. Working out why took far longer than anybody expected, and the popular…
There is a useful principle about signals that applies well beyond sound, and whistles are the clearest everyday demonstration of it.
The principle is that being heard is a matter…
Light leaves every point of a subject in all directions. A lens collects some of that and reconverges it, and the entire craft is built on the properties and failures…
There is a useful exercise in considering how recently an ordinary thing became ordinary, and fire on demand is the most striking example available.
Fire itself is extremely old. Reliable…