 Examples of three common spring types, Extension spring, Compression spring, and Torsion spring Image by User:Renard~enwiki, via Wikimedia Commons. Licensed CC BY-SA 3.0 |
HelixHelix Helix Space curve that winds around a line For other uses, see Helix (disambiguation). A helix (/ˈhiːlɪks/; pl. helices) is a shape like a cylindrical coil spring or the thread of a machine screw. It is a type of smooth skew curve with tangent lines at a constant angle to a fixed axis. Helices are important in biology, as the DNA molecule is formed as two intertwined helices, and many proteins have helical substructures, known as alpha helices. The word helix comes from the Greek word ἕλιξ, "twisted, curved".[1] A "filled-in" helix – for example, a "spiral" (helical) ramp – is a surface called a helicoid.[2] (l-r) Tension, compression and torsion coil springs A machine screw The right-handed helix… (Source: Wikipedia)
|
