Rust - The Longest War

(Norsk)

(image from Amazon.com)

Jonathan Waldman has written a book called 'Rust - The Longest War', and not surprisingly, it is about corrosion. But not from a purely professional, materials science perspective. Waldman is more of a journalist than a writer of professional literature, and it shows in the way he promotes the more human aspects in the book. The people he writes about are presented well and often with several background stories. 

Am amusing thin, red line he has managed to weave through the entire book, is short comments every now and again about the mustaches of some of the men he writes about. This is something he also makes a point of on his web page, where it is written at the bottom: {Made while sporting a mustache}.

In addition he manages to make a subject that can sound really dull, to become quite interesting. After having read the book, you will not have gained any professional knowledge to use in your work, but you will have a good insight into into how big a part of our lives are affected by corrosion, and that it actually is possible to combat it.

If you like to read books, I heartily recommend this one, which can be obtained from i.e. Amazon, or maybe it is possible to borrow it in a library nearby. If you prefer to listen to audiobooks, that is also fully possible, and you can use i.e. Audible to get it.

Suspension

(Norsk)
Destin, from one of my Youtube-channel favourites, Smarter Every Day, has recently uploaded a new clip which you can see at the bottom of this post. Amongst other things it show a suspension system works. One of the simplest and most commonplace examples of using a spring suspension system is a standard ballpoint pen. In my case, it is my trusty pen from NITO (the Norwegian Society of Engineers and Technologists):

When you push a spring together, you notice that that the resistance grows greater. This is because the force needed comes from this expression: F = cx. Here c is a constant for this specific spring, depending on the shape and material of the specific spring. As shown below x is the distance the end of the spring has moved compared to the initial position.

So, the more you compress the spring, the larger x becomes, and the larger the needed force also becomes. The same happens in a cylinder where you push the piston inwards. Here the force needed comes from the expression: F = pA, where p is the pressure and A is the area of the piston head. When the volume on the inside decreases, the pressure increases, and so also does the force necessary to push the piston further.

But, as Destin and the guys from NASA show in the clip below, a way to avoid that increase in resistance, is to use a cylinder with vacuum instead. The vacuum remains constant, even though the volume increases as you pull the piston outwards, and thus the resistance remains the same. Brilliant!