More physics revision today. Pressure, density, and ideal gases. No, I don't know what they are either. Well, not to any great extent. Pressure is... the force that is exerted over a certain area. Density has to do with packed-togetherness of particles, but I'm sure there's more to it than that. Ideal gases.... strange name. Something about the constant random motion of gas particles. I don't quite know why they're 'ideal'. Maybe normal particles don't do this?
The photograph is my first attempt at entering a day-of-the-week challenge, abstract Thursday, with the theme of patterns. It is a scarf I knitted (on a knitting machine, using the punchcard technique) in pink lambswool.