Everything is built around a solid form, and everything afterwards is a set of conflicting requirements settled in a particular way. Here are fifteen decisions inside any pair.
1. It…
There is a demonstration that has been used to teach chemistry for well over a century, and it works because a candle is far more complicated than it looks.
The…
There is a small category of objects that are fully explained by one diagram, and this is one of them.
A vacuum flask is a container inside another container, with…
Two materials are held apart in a state where one wants to give up electrons and the other wants to take them, and the separation is the entire trick. Here…
The film is not a solid thing. It is a layer of water held between two surfaces, and everything a bubble does - its shape, its colours, its lifespan and…
There is a question about corrosion that people rarely ask and that turns out to be the whole subject.
The question is not why metals corrode. Almost all of them…