Space is not empty. It contains very tenuous gases, plasmas, and various types of radiation, like light, infrared, ultraviolet, X rays, etc. As you note, we’re measuring the average speed of randomly ...

Think of a cake. When you put it in the oven, it starts off at a particular volume and then, an hour later, it has risen to perhaps double its size. It is obvious what has happened – the air bubbles ...

The liquid state of matter is an intermediate phase between solid and gas. Like the particles of a solid, particles in a liquid are subject to intermolecular attraction; however, liquid particles have ...