Physics:Structures
In ancient times， huge monuments were built of solid rocks. As engineering techniques improved， hollow structures could be built by using less materials and labour. Nowadays we've learnt about the forces within structures， and can build with the minimum amount of material. A structure has a variety of forces within it， for example， shear force， torsion， tension， to name just a few.
- Added：2006
- Country：Australia
- Duration：23
- Time of update：2011/8/15 15:20:57